Washington (CNN) Pope Francis challenged America Thursday to embrace millions of undocumented immigrants and join a global campaign against climate change and poverty, wading undaunted into the nation's volatile politics in a historic address to Congress.

Francis also called for a fairer world economy, the abolition of the death penalty, the protection of ethnic and religious minorities, the outlawing of the global "blood" trade in arms and the protection of the family in a speech sure to please liberals.

The speech underscored the emergence of Pope Francis as a global political leader -- rather than a moral or spiritual voice alone. His boldness in staking out positions on the nation's most pressing issues could reverberate through Capitol Hill and the 2016 presidential race in the months to come.

Practicing what he preached, the wildly popular pontiff, who has drawn thousands onto the streets along with blanket media coverage during his U.S. visit, then headed to pray and eat with homeless people and to pose for selfies with his adoring flock.

The Pope, who was greeted by cheers as he stepped onto the floor of the House of Representatives and received several standing ovations and sustained applause during his address, did not scold lawmakers -- his tone was more akin to that of a sermon or a pep talk. But he did not shirk from delivering blunt political messages.

Photos: Pope Francis in the United States Photos: Pope Francis in the United States Pope Francis waves from the top of the steps as he prepares to depart Philadelphia International Airport on Sunday, September 27, on his way back to Rome. The Pope has been on a six-day visit to the United States, with stops in Washington, New York and Philadelphia. Hide Caption 1 of 50 Photos: Pope Francis in the United States Pope Francis greets families at the conclusion of Mass at the World Meeting of Families at Benjamin Franklin Parkway in Philadelphia on September 27. Hide Caption 2 of 50 Photos: Pope Francis in the United States A huge crowd gathers to celebrate Mass with Pope Francis on September 27 in Philadelphia. Hide Caption 3 of 50 Photos: Pope Francis in the United States Pope Francis celebrates Mass at the World Meeting of Families at Benjamin Franklin Parkway in Philadelphia on September 27. Hide Caption 4 of 50 Photos: Pope Francis in the United States Pope Francis waves to the crowd from the popemobile during a parade along the Benjamin Franklin Parkway before Mass on September 27 in Philadelphia. Hide Caption 5 of 50 Photos: Pope Francis in the United States Pope Francis waves to the audience as he leaves Saint Charles Borromeo Seminary in Wynnewood, Pennsylvania, after addressing bishops on September 27. Hide Caption 6 of 50 Photos: Pope Francis in the United States Aretha Franklin performs as Pope Francis looks on during the Festival of Families on September 26 in Philadelphia. Hide Caption 7 of 50 Photos: Pope Francis in the United States Pope Francis takes the stage at the Festival of Families on September 26 in Philadelphia. Hide Caption 8 of 50 Photos: Pope Francis in the United States Pope Francis speaks in front of Independence Hall, from the lectern used by President Abraham Lincoln during the Gettysburg Address, on Saturday, September 26, in Philadelphia. Hide Caption 9 of 50 Photos: Pope Francis in the United States Pope Francis rides in the Popemobile along Independence Mall before delivering a speech outside Independence Hall on September 26. Hide Caption 10 of 50 Photos: Pope Francis in the United States Residents in decorated apartment windows await the arrival of Pope Francis near Independence Mall on September 26. Hide Caption 11 of 50 Photos: Pope Francis in the United States Pope Francis blesses Communion during a Mass at Cathedral Basilica of Saints Peter and Paul, Saturday, September 26, in Philadelphia. Hide Caption 12 of 50 Photos: Pope Francis in the United States Pope Francis delivers Mass before a crowd of more than 2,000, consisting largely of priests, women religious and deacons on September 26. Hide Caption 13 of 50 Photos: Pope Francis in the United States Members of the choir arrive at Cathedral Basilica of Saints Peter and Paul prior to the arrival of Pope Francis on September 26. Hide Caption 14 of 50 Photos: Pope Francis in the United States Pope Francis kisses and blesses Michael Keating, 10, of Elverson, Pennsylvania, after arriving in Philadelphia on September 26. Keating has cerebral palsy and is the son of Chuck Keating, director of the Bishop Shanahan High School band, which performed at Pope Francis' airport arrival. Hide Caption 15 of 50 Photos: Pope Francis in the United States The faithful receive communion at the snack bar during Mass at Madison Square Garden on September 25. Hide Caption 16 of 50 Photos: Pope Francis in the United States Pope Francis celebrates Mass at Madison Square Garden on Friday, September 25, in New York City. Hide Caption 17 of 50 Photos: Pope Francis in the United States A crucifix hangs above members of the clergy during Mass at Madison Square Garden on September 25. Hide Caption 18 of 50 Photos: Pope Francis in the United States Pope Francis rides through New York's Central Park on September 25. Francis addressed the U.N. General Assembly and will head to Philadelphia this weekend for the World Meeting of Families, a large Catholic event expected to draw nearly 1 million pilgrims. Hide Caption 19 of 50 Photos: Pope Francis in the United States Pope Francis greets the crowd in New York's East Harlem Neighborhood on September 25. Hide Caption 20 of 50 Photos: Pope Francis in the United States Pope Francis places a white rose at the 9/11 memorial in New York on September 25. Hide Caption 21 of 50 Photos: Pope Francis in the United States Francis attends a multireligious service at the 9/11 memorial. Hide Caption 22 of 50 Photos: Pope Francis in the United States The Pope arrives at the U.N. General Assembly to give his speech. Hide Caption 23 of 50 Photos: Pope Francis in the United States Francis gives a thumbs-up after leading an evening prayer service Thursday, September 24, at St. Patrick's Cathedral in New York. Hide Caption 24 of 50 Photos: Pope Francis in the United States Nuns celebrate at St. Patrick's Cathedral as they wait for the arrival of Pope Francis. Hide Caption 25 of 50 Photos: Pope Francis in the United States Francis greets crowds as he arrives at St. Patrick's Cathedral. Hide Caption 26 of 50 Photos: Pope Francis in the United States Crowds welcome Pope Francis to New York on September 24 after his arrival at John F. Kennedy International Airport. Hide Caption 27 of 50 Photos: Pope Francis in the United States A Pope Francis doll amuses the man himself at John F. Kennedy International Airport. Hide Caption 28 of 50 Photos: Pope Francis in the United States Pope Francis stops to look at a sculpture of Spanish-born missionary Junipero Serra at the U.S. Capitol in Washington on September 24. The Pope canonized Serra during a Mass the day before. Hide Caption 29 of 50 Photos: Pope Francis in the United States Members of Congress accompany Pope Francis on the Speaker's Balcony on Capitol Hill on September 24. Hide Caption 30 of 50 Photos: Pope Francis in the United States Congressional staffers and guests strain to view and photograph the Pope at the Capitol. Hide Caption 31 of 50 Photos: Pope Francis in the United States Francis blesses a child at the Capitol. Hide Caption 32 of 50 Photos: Pope Francis in the United States Pope Francis addresses a joint meeting of the U.S. Congress on September 24. Vice President Joe Biden and House Speaker John Boehner sit behind him in the House chamber. Hide Caption 33 of 50 Photos: Pope Francis in the United States Francis is the first Pope to address a joint meeting of Congress. Hide Caption 34 of 50 Photos: Pope Francis in the United States Boehner welcomes Pope Francis before his speech to Congress. Hide Caption 35 of 50 Photos: Pope Francis in the United States Pope Francis canonizes Serra during a Mass in Washington on Wednesday, September 23. Hide Caption 36 of 50 Photos: Pope Francis in the United States The Pope celebrates Mass at the National Shrine of the Immaculate Conception on September 23. Hide Caption 37 of 50 Photos: Pope Francis in the United States Nuns wait for Pope Francis to arrive inside the Basilica of the National Shrine of the Immaculate Conception. Hide Caption 38 of 50 Photos: Pope Francis in the United States Pope Francis greets crowds during his parade in Washington on September 23. Hide Caption 39 of 50 Photos: Pope Francis in the United States Pope Francis reaches out to bless a child during the parade in Washington. Hide Caption 40 of 50 Photos: Pope Francis in the United States President Barack Obama hosts the Pope in the Oval Office of the White House on September 23. Hide Caption 41 of 50 Photos: Pope Francis in the United States Obama, the Pope and first lady Michelle Obama greet the crowd during an arrival ceremony on the South Lawn of the White House on September 23. Hide Caption 42 of 50 Photos: Pope Francis in the United States Pope Francis addresses guests on the South Lawn of the White House. Hide Caption 43 of 50 Photos: Pope Francis in the United States People wave U.S. and Vatican flags as they wait for the Pope's arrival at the White House on September 23. Hide Caption 44 of 50 Photos: Pope Francis in the United States Early on September 23, people gather along Pope Francis' parade route in Washington. Hide Caption 45 of 50 Photos: Pope Francis in the United States Pope Francis departs from Andrews Air Force Base in Maryland shortly after his flight landed on Tuesday, September 22. Hide Caption 46 of 50 Photos: Pope Francis in the United States Pope Francis waves from his car at Andrews Air Force Base. Hide Caption 47 of 50 Photos: Pope Francis in the United States Pope Francis is escorted by the Obamas and their daughters after arriving in the country. Hide Caption 48 of 50 Photos: Pope Francis in the United States Clergy members brace for the wind as they stand on the tarmac at Andrews Air Force Base. Hide Caption 49 of 50 Photos: Pope Francis in the United States The Pope waves at Obama and his family. Hide Caption 50 of 50

He laid out an implicit counter-argument to some conservatives, including 2016 Republican front-runner Donald Trump, who believes that the more than 10 million undocumented immigrants in the country should be deported. He implied that to do so would repudiate America's founding purpose as a nation born of immigrants seeking a better life.

"We, the people of this continent, are not fearful of foreigners, because most of us were once foreigners," he said, as Vice President Joe Biden and an often tearful Republican House Speaker John Boehner, both Catholics, watched from the dais.

"I say this to you as the son of immigrants, knowing that so many of you are also descended from immigrants," Francis told the audience of lawmakers, top military brass, Supreme Court justices and Cabinet members on the floor of the House.

He made a clear connection between undocumented immigrants in the U.S. and the exodus of Syrians and others into Europe from wars raging in the Middle East.

"On this continent, too, thousands of persons are led to travel north in search of a better life for themselves and for their loved ones, in search of greater opportunities," he said of migrants from Central and South America, indicating they needed to be treated as people seeking refuge rather than as exploiting the United States' porous borders.

In an apparent rebuke to politicians who have criticized the tide of undocumented immigrants, he continued, "We must not be taken aback by their numbers, but rather view them as persons, seeing their faces and listening to their stories, trying to respond as best we can to their situation."

Then, citing Scripture to drive home his argument, Francis said: "Let us remember the Golden Rule: 'Do unto others as you would have them do to you.'"

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He called on often warring lawmakers to honor the example of their greatest national heroes, like Martin Luther King, Jr. and Abraham Lincoln.

Francis appeared to reflect on news coverage of racial violence over the past year and a debate over the place of Muslims in U.S. society that arose in recent weeks.

Citing Martin Luther King's "dream of full rights for all their brothers and sisters," he urged Americans in the 50 minute speech to remember the civil rights icon's legacy of "liberty in plurality and non-exclusion."

Referring to turmoil tearing apart the Middle East, Francis warned the world was increasingly a place of fundamentalism and "brutal atrocities" sometimes committed in the name of religion, but he warned against a simplistic world view pitting good versus evil or "the righteous and the sinners."

"We know that in the attempt to be freed of the enemy without, we can be tempted to feed the enemy within," Francis warned.

Clearly conscious that many conservatives in Congress are skeptical that mankind is contributing to global warming, he called for a courageous and responsible effort to avert "environmental deterioration caused by human activity" and said Congress had an "important role to play."

He also praised efforts in recent months to "help overcome historic differences linked to painful episodes of the past," a passage that President Barack Obama's supporters may take as approval of his controversial policies towards Cuba and Iran.

Amid criticism that he is overly critical of global capitalism and dismisses its place in lifting millions of people out of poverty, Francis acknowledged that "business is a noble vocation, directed to producing wealth and improving the world."

Photos: Pope Francis Photos: Pope Francis Colombian President Juan Manuel Santos, left, reads aloud words engraved on a pen as he meets with Pope Francis at the Vatican, Friday, December 16, 2016. The words "The bullets have written our past, education will write our future" are engraved on the pen, made from a recycled bullet once used in the civil war between the Colombian government and the Revolutionary Armed Forces of Colombia (FARC). The pen was later used to sign the peace agreements between the parties earlier this year. Santos, who was awarded the 2016 Nobel Peace Prize for his efforts to end the region's longest-running conflict, presented Pope Francis with the pen. Hide Caption 1 of 44 Photos: Pope Francis Pope Francis accepts a letter from a child he visited at a pediatric hospital in Rome on Thursday, December 15, 2016. Hide Caption 2 of 44 Photos: Pope Francis Pope Francis poses with members of the International Catholic Rural Association at the Vatican on Saturday, December 10, 2016. Hide Caption 3 of 44 Photos: Pope Francis Pope Francis salutes the faithful upon his arrival in St. Peter's Square at the Vatican for the Special Jubilee Papal Audience on Saturday, October 22, 2016. Hide Caption 4 of 44 Photos: Pope Francis Pope Francis looks on with joy as he releases a dove as a symbol of peace during a meeting with the Assyrian Chaldean community at the Catholic Chaldean Church of St. Simon Bar Sabbae in Tbilisi, Georgia, on September 30, 2016. Hide Caption 5 of 44 Photos: Pope Francis Pope Francis passes the main entrance to Auschwitz-Birkenau, the former concentration camp in Poland, on Friday, July 29, 2016. The Pope was there to pay tribute to those who died in the Holocaust. Hide Caption 6 of 44 Photos: Pope Francis Pope Francis looks on as Catholicos of All Armenians Karekin II celebrates the Divine Liturgy at the Apostolic Cathedral in Etchmiadzin, outside Yerevan, Armenia, on June 26, 2016. Hide Caption 7 of 44 Photos: Pope Francis Pope Francis arrives to celebrate an extraordinary Jubilee Audience as part of ongoing celebrations of the Holy Year of Mercy in St. Peter's Square in Vatican City on May 14, 2016. Hide Caption 8 of 44 Photos: Pope Francis Pope Francis hugs a child at the Moria refugee camp on the Greek island of Lesbos on Saturday, April 16, 2016. Pope Francis received an emotional welcome on the island during a visit showing solidarity with migrants fleeing war and poverty. Hide Caption 9 of 44 Photos: Pope Francis Pope Francis confesses in St. Peter's Basilica during the Vatican's Penitential Celebration on Friday, March 4, 2016. Hide Caption 10 of 44 Photos: Pope Francis Pope Francis tries on a traditional sombrero he received as a gift from a Mexican journalist on Friday, February 12, 2016, aboard a flight from Rome to Havana, Cuba. The voyage kicked off his weeklong trip to Mexico. With his penchant for crowd-pleasing and spontaneous acts of compassion, Pope Francis has earned high praise from fellow Catholics and others since he succeeded Pope Benedict XVI in March 2013. Hide Caption 11 of 44 Photos: Pope Francis Pope Francis arrives for his visit with prisoners in Santa Cruz, Bolivia, on Friday, July 10, 2015. The Pope emphasized the plight of the poor during his eight-day tour of South America, which also included stops in Ecuador and Paraguay. Hide Caption 12 of 44 Photos: Pope Francis Bolivian President Evo Morales presents the Pope with a gift of a crucifix carved into a wooden hammer and sickle -- the Communist symbol uniting laborers and peasants -- in La Paz, Bolivia, on Wednesday, July 8, 2015. Hide Caption 13 of 44 Photos: Pope Francis Pope Francis greets a crowd of Italian Catholic boy scouts and girl guides at St. Peter's Square on Saturday, June 13, 2015. Hide Caption 14 of 44 Photos: Pope Francis Russian President Vladimir Putin, left, meets Pope Francis at the Vatican on Wednesday, June 10, 2015. The Pope gave Putin a medallion depicting the angel of peace, Vatican spokesman Federico Lombardi said. The Vatican called it "an invitation to build a world of solidarity and peace founded on justice." Lombardi said the pontiff and President talked for 50 minutes about the crisis in Ukraine and violence in Iraq and Syria. Hide Caption 15 of 44 Photos: Pope Francis Pope Francis meets with Cuban President Raul Castro at the Vatican on Sunday, May 10, 2015. Castro thanked the Pope for his role in brokering the rapprochement between Havana and Washington. Hide Caption 16 of 44 Photos: Pope Francis The Pope prays face down on the floor of St. Peter's Basilica during Good Friday celebrations at the Vatican on Friday, April 3, 2015. Hide Caption 17 of 44 Photos: Pope Francis Pope Francis touches a child's face as he arrives for a meeting at the Vatican on Friday, March 6, 2015. Hide Caption 18 of 44 Photos: Pope Francis Hindu priest Kurukkal SivaSri T. Mahadeva presents a shawl to Pope Francis in Colombo, Sri Lanka, on Tuesday, January 13, 2015. Hide Caption 19 of 44 Photos: Pope Francis The Pope attends Christmas Eve Mass at St. Peter's Basilica in Vatican City in December 2014. Hide Caption 20 of 44 Photos: Pope Francis Pope Francis and Ecumenical Patriarch Bartholomew I address the faithful in Istanbul on Sunday, November 30, 2014. Hide Caption 21 of 44 Photos: Pope Francis Pope Francis speaks during the feast-day Mass while on a one-day trip to Italy's Calabria region in June 2014. The Pope spoke out against the Mafia's "adoration of evil and contempt for the common good," and declared that "Mafiosi are excommunicated, not in communion with God." Hide Caption 22 of 44 Photos: Pope Francis Pope Francis prays next to a rabbi at the Western Wall in Jerusalem's Old City in May 2014. The Pope went on a three-day trip to the Holy Land , and he was accompanied by Jewish and Muslim leaders from his home country of Argentina. Hide Caption 23 of 44 Photos: Pope Francis The Pope meets the faithful as he visits the Roman Parish of San Gregorio Magno in April 2014. Hide Caption 24 of 44 Photos: Pope Francis Queen Elizabeth II and Prince Philip, Duke of Edinburgh, have an audience with the Pope during their one-day visit to Rome in April 2014. Hide Caption 25 of 44 Photos: Pope Francis Francis speaks with US President Barack Obama at the Vatican in March 2014. Hide Caption 26 of 44 Photos: Pope Francis The Pope blesses the altar at Rome's Basilica of Santa Sabina as he celebrates Mass on Ash Wednesday in March 2014. Hide Caption 27 of 44 Photos: Pope Francis Daniele De Sanctis, a 19-month-old dressed as the pope, is handed to Francis as the pontiff is driven through the crowd in St. Peter's Square in February 2014. Hide Caption 28 of 44 Photos: Pope Francis Wind blows the papal skullcap off Pope Francis' head in February 2014. Hide Caption 29 of 44 Photos: Pope Francis A lamb is placed around Francis' neck in January 2014 as he visits a living nativity scene staged at a church on the outskirts of Rome. Hide Caption 30 of 44 Photos: Pope Francis Pope Francis meets with Pope Emeritus Benedict XVI at the Vatican in December 2013. Benedict surprised the world by resigning "because of advanced age." It was the first time a pope has stepped down in nearly 600 years. Hide Caption 31 of 44 Photos: Pope Francis Pope Francis marked his 77th birthday in December 2013 by hosting homeless men at a Mass and a meal at the Vatican. One of the men brought his dog. Hide Caption 32 of 44 Photos: Pope Francis Pope Francis embraced Vinicio Riva, a disfigured man who suffers from a non-infectious genetic disease, during a public audience at the Vatican in November 2013. Riva then buried his head in the Pope's chest. Hide Caption 33 of 44 Photos: Pope Francis Pope Francis jokes in November 2013 with members of the Rainbow Association Marco Iagulli Onlus, which uses clown therapy in hospitals, nursing homes and orphanages. Hide Caption 34 of 44 Photos: Pope Francis A young boy hugs Francis as he delivers a speech in St. Peter's Square in October 2013. The boy, part of a group of children sitting around the stage, played around the Pope as the Pope continued his speech and occasionally patted the boy's head. Hide Caption 35 of 44 Photos: Pope Francis Francis has eschewed fancy cars. Here, Father Don Renzo Zocca, second from right, offers his white Renault 4L to the Pope during a meeting at the Vatican in September 2013. Hide Caption 36 of 44 Photos: Pope Francis Francis has his picture taken inside St. Peter's Basilica with youths who came to Rome for a pilgrimage in August 2013. Hide Caption 37 of 44 Photos: Pope Francis During an impromptu news conference in July 2013, while on a plane from Brazil to Rome, the Pope said about gay priests, "Who am I to judge?" Many saw the move as the opening of a more tolerant era in the Catholic Church. Hide Caption 38 of 44 Photos: Pope Francis Crowds swarm the Pope as he makes his way through World Youth Day in Rio de Janeiro in July 2013. According to the Vatican, 1 million people turned out to see the Pope. Hide Caption 39 of 44 Photos: Pope Francis Francis frees a dove in May 2013 during his weekly general audience in St. Peter's Square. Hide Caption 40 of 44 Photos: Pope Francis Francis embraces a young boy with cerebral palsy in March 2013 -- a gesture that many took as a heartwarming token of the Pope's self-stated desire to "be close to the people." Hide Caption 41 of 44 Photos: Pope Francis The Pope washes the feet of juvenile offenders, including Muslim women, as part of Holy Thursday rituals in March 2013. The act commemorates Jesus' washing of the Apostles' feet during the Last Supper. Hide Caption 42 of 44 Photos: Pope Francis Francis stands at the reception desk of the Domus Internationalis Paulus VI residence on March 14, 2013, where he paid the bill for his stay during the conclave that would elect him leader of the world's 1.2 billion Catholics. Hide Caption 43 of 44 Photos: Pope Francis Francis, formerly known as Argentine Cardinal Jorge Mario Bergoglio, was elected the Roman Catholic Church's 266th Pope in March 2013. The first pontiff from Latin America was also the first to take the name Francis. Hide Caption 44 of 44

But he cautioned that wealth should be shared and geared to "the creation of jobs as an essential part of its service to the common good."

He did, however, cut one section of his prepared speech, in which he referred to the Declaration of Independence and said that politics should not be a "slave to the economy and finance."

Vatican spokesman Father Lombardi later said the Pope made a "little oversight" and skipped those lines by mistake, with the prepared text of the speech to Congress remaining the official version.

The Pope also counseled members of the unpopular and divided Congress of the need to move forward together in a generous spirit of fraternity.

"The challenges facing us today call for a renewal of that spirit of cooperation, which has accomplished so much good throughout the history of the United States," he said, and called on America to act on his appeals.

"The complexity, the gravity and the urgency of these challenges demand that we pool our resources and talents and resolve to support one another, with respect for our differences and our convictions of conscience," he said.

Francis, who will take part Sunday in a World Meeting of Families in Philadelphia on the last stop of his trip to the United States, also made an oblique reference Thursday to the increasing prevalence of same-sex marriage, which the Supreme Court endorsed nationwide earlier this year.

"I cannot hide my concern for the family, which is threatened, perhaps as never before, from within and without," Francis said. "Fundamental relationships are being called into question, as is the very basis of marriage and the family."

The Pope drew cheers, especially from the Republican side of the House, when he spoke of the need to "protect and defend human life at every stage of its development," in a reference to abortion.

But he earned only a smattering of applause when he said that reverence for life also means supporting the global abolition of the death penalty. Francis threw his weight behind efforts to pass criminal justice reform, saying society "can only benefit from the rehabilitation of those convicted of crimes."

There were also signs of a partisan split in the chamber when Francis mentioned global warming and immigration, which Democrats applauded while many Republicans did not.

But despite the progressive content of his speech, Francis appeared to avoid offending anyone.

"We found ourselves standing up and sitting down more than what we anticipated," Republican Sen. Mike Rounds told CNN's Dana Bash. Former GOP vice presidential nominee Rep. Paul Ryan told CNN that it would be wrong to treat the speech as "a sort of laundry list of policies."

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Democratic presidential candidate Sen. Bernie Sanders, meanwhile, welcomed the liberal content of an address that he described as dignified and nonpartisan.

After his speech, Francis appeared on the Speaker's balcony along with bipartisan leaders of Congress and smiled broadly at the thousands of people gathered below on the National Mall. He singled out children for special mention, and asked even those who had no faith and could not pray to send him good wishes.

After making brief remarks in Spanish on the balcony, Francis concluded by declaring in English, "God bless America!"

He then went to St Matthew's Cathedral to pray with homeless people. He was mobbed by admirers outside, smiling broadly at children and posing for pictures shot on mobile phones, as Secret Service agents and Vatican officials cleared his way through the crowd.

"In prayer, there are no rich or poor people," the pontiff said in the church. "There are sons and daughters."

"Today I want to be one with you," he said. "I need your support, your closeness."

Francis later flew out of Joint Base Andrews outside Washington and headed to New York, where he will ride his popemobile through Manhattan and lead evening prayers at St Patrick's Cathedral before speaking at the United Nations on Friday. He will conclude his six-day visit to the United States in Philadelphia on Sunday.