President Donald Trump and Ukrainian President Volodymyr Zelenskyy met at the Vatican Saturday before attending the funeral of Pope Francis, according to the White House.

An image shared by the White House shows President Trump and Zelenskyy seated face-to-face in chairs in St. Peter's Basilica in Vatican City. Major details of the leaders' discussion have not yet been released. The two leaders spoke for about 15 minutes before the funeral.

The White House called the discussion "very productive."

“We discussed a lot one on one. Hoping for results on everything we covered," Zelenskyy posted on social media. "Protecting lives of our people. Full and unconditional ceasefire. Reliable and lasting peace that will prevent another war from breaking out. Very symbolic meeting that has potential to become historic, if we achieve joint results. Thank you."

Both heads of state were among 12 reigning monarchs and 55 heads of state the Vatican said attended Francis' funeral.

President Trump reportedly returned to the airport immediately after the funeral to prepare for the return flight to the U.S.

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The meeting comes as President Trump continues to push Russia and Ukraine to meet and work toward a peace deal.

In comments posted on social media Friday, President Trump said he believes a deal between the two countries is close.

"Success seems to be in the future" he wrote, and later in the day: "They are very close to a deal, and the two sides should now meet, at very high levels, to 'finish it off.' Most of the major points are agreed to. Stop the bloodshed, NOW."

But in comments to Time Magazine also published Friday, President Trump said "Crimea will stay with Russia."

Ukrainian officials say a plan reportedly proposed by the U.S. to officially recognize Russian control of Crimea is unacceptable.

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