David Jackson

USA TODAY

WASHINGTON — No one will support the intelligence community more than he will, President Trump told a crowd at CIA headquarters Saturday, while he also attacked the news media for reporting that he had a "feud" with intelligence agencies.

While at the CIA, Trump also blasted media coverage of his inauguration on Friday — a protest angrily echoed later by press secretary Sean Spicer, who accused reporters of deliberate "false reporting" of attendance and interest in Trump's swearing-in.

While Trump has clashed with intelligence officials in recent weeks over investigations into Russian election activity, the new president told intelligence agency employees that "you're going to get so much backing" from his administration.

Describing the CIA as a key to victory over Islamic State-style terrorists, Trump also talked politics during his visit, telling employees that he got the most votes in last year's election from members of the military, law enforcement and intelligence communities, and "probably almost everybody in this room voted for me" in the election,

"We're all on the same wavelength, folks," Trump said while standing at a memorial wall honoring CIA agents who have given their lives in service to the nation.

Trump's CIA trip — his first official visit as chief executive — came hours after he attended a National Prayer Service at Washington National Cathedral, nearly 24 hours after being sworn in as the nation's 45th president.

Meanwhile, thousands marched in the streets of Washington and other cities across the globe to protest his presidency and even challenge its legitimacy.

In other second-day developments:

• The White House announced that British Prime Minister Theresa May will meet with Trump in Washington late next week.

• Spicer said Trump will meet with Mexico President Enrique Peña Nieto on Jan. 31 and that the two leaders spoke by phone about trade, immigration, security and other issues.

• Trump also spoke with Canadian Prime Minister Justin Trudeau, a partner along with Mexico in the North American Free Trade Agreement that Trump has vowed to change.

• Trump repeated a campaign line that the United States should have "kept"' Iraq's oil after the 2003 invasion, saying that might have blocked the rise of the Islamic State. He added: "Maybe we'll have another chance." The president again suggested he opposed the Iraq war, though interviews at the time indicated otherwise.

• The Trump Department of Justice said the president is within his rights to hire son-in-law Jared Kushner as a White House adviser; a Justice memorandum said a nepotism law passed by Congress does not apply to the executive branch.

• Trump again took to social media, tweeting that "I am honored to serve you, the great American People, as your 45th President of the United States!"

Trump's visit to CIA headquarters in Virginia resembled something of a peace mission.

During the transition between election and inauguration, leaders of the intelligence community said Russia engineered the hacking in an effort to help Trump, while Trump and supporters said other countries could have been involved. He also claimed the intelligence community leaked damaging information on him, including allegations out of Russia. (Trump later acknowledged that Russia was behind the hacking but that it didn't affect the counting of votes.)

In his appearance before CIA employees, Trump blamed the media for what he called false reporting of a "feud" with intelligence, saying that "I have a running war with the media; they are among the most dishonest human beings on earth."

He also attacked media coverage of parts of his Inauguration Day, saying media outlets played down the size of the crowd he drew.

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Democrats cited claims against Russia and the Trump campaign in reacting to the candidate's CIA visit.

“After he finished ranting about crowd sizes on the National Mall, I hope President Trump sat down for an interview with the CIA to help with their investigation into his team’s possible collusion with the Kremlin to win the election," said Zac Petkanas, a senior adviser to the Democratic National Committee. "Next, he can sit down with the FBI who have sought warrants to monitor his team for the same reason.”

Earlier in the day, Trump tweeted praise for Friday's inaugural events (and one news network's coverage of it).

"A fantastic day and evening in Washington D.C.," Trump said. "Thank you to @FoxNews and so many other news outlets for the GREAT reviews of the speech!"

Others criticized Trump's inaugural address, calling it too dark and pessimistic. Citing the specters of crime, poor education, and shuttered factories, the new president told his constituents, "this American carnage stops right here and stops right now."

A New York Times editorial said Trump ignored positive developments in law enforcement and economic opportunity, and that "the new president offered a tortured rewrite of American history — ignoring the injustices of the past as well as the nation’s economic resilience and social achievements in recent decades."

Trump used his personal Twitter feed for posts on Saturday, rather than the official @POTUS one.

The new president extolled his Twitter use during one of the inaugural balls Friday night, asking the crowd, "should I keep the Twitter going or not?" When supporters roared their approval, Trump replied, "I think so. You know, the enemies keep saying, 'oh, that’s terrible.' But it’s a way of bypassing dishonest media.”

The Trump administration also ordered a regulatory freeze, similar to the ones imposed imposed by presidents Obama and Bush at the start of their terms.

Newly Trump-led agencies and departments are also starting to assert their authority.

On another social media front, The Washington Post reported that the administration ordered the Interior Department to shut down its Twitter account after it opposed unflattering pictures of the size of the crowd at Trump's inaugural, much smaller than the one Obama had in 2009.

“All bureaus and the department have been directed by incoming administration to shut down Twitter platforms immediately until further notice,” said an email obtained by the Post.

Read more:

Analysis: Trump’s short, dark and defiant inaugural address

Fact check: President Trump's inaugural address