U.S. President Donald Trump said he plans to speak to Russian President Vladimir Putin on Tuesday and discuss ending the war in Ukraine.

"I'll be speaking to President Putin on Tuesday. A lot of work's been done over the weekend," Trump told reporters on Air Force One during a late flight back to the Washington area from Florida.

"We want to see if we can bring that war to an end. Maybe we can, maybe we can't, but I think we have a very good chance," Trump said.

Trump is trying to win Putin's support for a 30-day ceasefire proposal that Ukraine accepted last week, as both sides continued trading heavy aerial strikes through the weekend and Russia moved closer to ejecting Ukrainian forces from their months-old foothold in the western Russian region of Kursk.

"We will be talking about land. We will be talking about power plants," Trump said, when asked about concessions. "I think we have a lot of it already discussed very much by both sides, Ukraine and Russia. We are already talking about that, dividing up certain assets."