A Vatican statement said the meeting was "cordial" and that the Vatican hoped there could be "serene collaboration" between the USA government and the American Catholic Church, including "assistance to immigrants".
The Vatican described the discussions as "cordial" and emphasised the two men s joint opposition to abortion and shared concern for persecuted Christians in the Middle East.
At 8:20 a.m., under an azure sky, the president's motorcade rolled into the courtyard of the Apostolic Palace.
For a president whose inner circle often shifts, Spicer's absence from the meeting was seen as an intentional snub, a source close to the White House told CNN.
Much was made in the media of their differences in the weeks leading up to the meeting.
While Trump flashed a wide grin, the Pope offered only a modest smile - his demeanor, business-like.
Correspondents said Mr Trump seemed subdued during their initial meeting, while Pope Francis was not as jovial as he sometimes was with world leaders.
The two men had never met before this morning but they have significant history having clashed publicly over subjects ranging from migration to unbridled capitalism and climate change. As many of us know, Pope Francis is pretty progressive and a very far cry from traditional Catholicism.
The first lady laughed and said "Yes". "Trump's bark is worse than his bite", said a senior Vatican official who was granted anonymity because he was not authorized to speak about the meeting. "I believe that I shouldn't do this".
"It's by a Roman artist, of an olive tree which is a symbol of peace", the Pope said, according to National Catholic Register blogger Edward Pentin. Can you spot the one in which the pontiff isn't smiling?More news: Police make sixth arrest after Manchester bomb attack
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Mr Trump responded: "We can use peace".
Hicks, a loyal aide who has been at Trump's side since before he announced his candidacy, was introduced to Pope Francis by the president as someone who has worked for him a long time.
The first lady knows her fashion - and how not to mess up a meeting at the Vatican with the wrong outfit.
North Atlantic Treaty Organisation insiders have admitted that no one is quite sure what message Mr Trump will deliver to the alliance.
Trump has expressed skepticism about global warming and possible causes, and he has promised changes to spur more coal and oil production in the U.S.
"Well, I'll be reading them", the US President said.
"Making tremendous progress", Trump told Belgian Prime Minister Charles Michel. Mrs. Trump visited children in the intensive care unit there, and she spent time praying alone in the hospital chapel, and laid flowers at the feet of the hospital's statue of Our Lady.
After a highly anticipated meeting, Pope Francis appears to have left his mark on President Donald Trump.