U.S. President Donald Trump said he believes his Russian counterpart Vladimir Putin is ready to end his war in Ukraine, speaking on the eve of Friday's summit between the men, but that peace would likely require at least a second meeting involving Ukraine's leader, Reuters reported.

Ukrainian President Volodymyr Zelenskiy and his European allies have intensified their efforts this week to prevent any deal between the U.S. and Russia emerging from Friday's summit in Alaska that leaves Ukraine vulnerable to future attack.

"I think President Putin will make peace, I think President Zelenskiy will make peace," Trump told reporters at the White House. "We'll see if they get along."

Trump has downplayed talk of a ceasefire emerging from the summit and speculated about a possible second meeting to come, involving more leaders, according to Reuters.