US President Barack Obama with Pope Francis as the pontiff was welcomed to the White House during a ceremony in Washington, D.C., on Wednesday. Reuters Pope Francis addressed a crowd at the White House on Wednesday morning, calling climate change an urgent problem in a Washington that has been reluctant to take steps to address the issue.

In his speech from the White House lawn, the start of his first tour of the United States, the pontiff talked, as many had expected, about the fight against climate change. He praised President Barack Obama for his proposals, which aim for the US to cut emissions by up to 28% over the next decade.

"Mr. President, I find it encouraging that you are introducing an initiative for reducing air pollution," Pope Francis said.

But to Pope Francis, Obama was clearly the exception in a Washington he hinted was not doing enough to deal with the issue. The pope said climate change was a "problem that can no longer be left to a future generation."

A few months ago, Pope Francis angered many Republicans and climate-change skeptics in the US when he called for global action to address the plight.

In remarks made earlier Wednesday, Obama addressed the pope's previous call for action.

"We support your call to all world leaders to support the communities most vulnerable to a changing climate and to come together to preserve our precious world for future generations," Obama said.

Climate change was not the only issue the leader of the Catholic Church addressed. At a time when immigration reform is a central theme of the 2016 presidential election, Pope Francis reminded the crowd that he, too, was the son of an immigrant.



Pope Francis greeting well-wishers while leaving the Apostolic Nunciature, the Vatican's diplomatic mission in Washington, on Wednesday. AP images "As the son of an immigrant, I'm happy to be a guest in this country, which was largely built by such families," he said.

But as many Republicans have been dismayed by the religious leader's embrace of some more left-leaning economic policies, his speech also included a nod to the right.

Of religious freedom, the pontiff said US bishops must "preserve and defend that freedom from everything that would threaten or compromise it." His reference alluded to the many differences with the administration on touchy social issues such as abortion rights and same-sex marriage.

Wednesday morning featured Pope Francis' first speech in Washington, D.C., before a meeting with Obama. On Thursday he plans to deliver a highly anticipated address to Congress.