U.S. President Donald Trump said on Saturday that talks aimed at ending the war in Ukraine may be going OK, but "there’s a point at which you just have to either put up or shut up."

Trump made the comment to reporters a day after he showed frustration with Russia and told it to "get moving" on reaching a deal.

"I think Ukraine-Russia might be going OK, and you’re going to be finding out pretty soon," Trump told reporters on Air Force One, but added that "there’s a point at which you just have to either put up or shut up and we'll see what happens."