A picture of their visit went viral shows Trump smiling whereas his wife and daughter along with the Pope Francis were standing morose and stiff.
Pope Francis and President Trump probably didn't talk about the budget, writes Maureen Fiedler. "A Christian would never say 'you will pay for that.' Never", the Pope had said while indirectly lashing out at Trump.
The CNN story notes that while senior White House officials claimed the Vatican is strict on admittance into its talks, "previous administration officials who helped orchestrate meetings between U.S. presidents and the Pope said that high-level Catholic staffers who expressed interest in attending the papal sessions were regularly accommodated".
During the election season a year ago, the pope had criticised the then-presidential candidate for his approach to immigration.
Trump, midway through his grueling nine-day maiden worldwide journey, met with the pontiff at the Vatican early Wednesday where the two will have a private audience laden with religious symbolism and ancient protocol. Reince Priebus, the White House chief of staff, and Stephen Bannon, Trump's chief strategist, had already returned to Washington after the initial stop in Saudi Arabia.
Like Melania Trump, former first ladies Laura Bush and Hillary Clinton have forgone headscarves when visiting the country.
According to an interview he gave a year ago, Trump is 1.88 metres tall (six foot two inches) and weighs 107 kilos (235 pounds).
In Israel, the Trumps visited the Western Wall, the holiest site where Jews can pray. Trump likely wore one out of respect. Many Orthodox Jewish women cover their hair as a sign of modesty. As well as the encyclical, the Pope also gave Trump a medallion engraved with an image of an olive tree as a "symbol of peace". Only royals are allowed the "privilege du blanc" - the so-called white privilege that dictates white outfits and white head coverings for queens and other royals when meeting the pontiff. "It was an honour to meet the Pope".
Adorned head-to-toe in black, Melania accompanied her husband to see Pope Benedict today.
The meeting between the leader of the free world and the head of the Catholic Church emphasised areas of agreement between the new administration and the Vatican. First Lady Laura Bush followed a similar custom during a 2006 papal audience.