United States President Donald Trump has said he will speak with Russian President Vladimir Putin on Tuesday about bringing an end to the war in Ukraine.

Speaking to reporters on Air Force One on Sunday, Trump said “a lot of work” had been done over the weekend.

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

Asked about what concessions were under consideration in the ceasefire talks, Trump said the discussions would include land and power plants.

“I think we have a lot of it already discussed very much by both sides, Ukraine and Russia,” he said.

“We’re already talking about that, dividing up certain assets.”

Trump’s comments came hours after a high-ranking Russian official was quoted in a local media report saying that any peace deal would preclude Ukraine’s NATO membership.

In an interview with Russian outlet Izvestia, Russian Deputy Foreign Minister Alexander Grushko said Moscow would need “ironclad security guarantees” to agree to a ceasefire.

“Only by establishing such guarantees can lasting peace in Ukraine be achieved and regional security strengthened overall. A neutral status for Ukraine and NATO countries refraining from accepting it as a member of the alliance should be part of these guarantees,” Grushko was quoted as saying.

“In fact, this provision was precisely outlined in the drafts of the mentioned agreements. As for discussions, they are not currently taking place, as there are no negotiations under way.”

Earlier on Sunday, Trump’s special envoy Steve Witkoff said, the two leaders planned to have a “really good and positive discussion” this week.

Washington is hoping to convince the sides to agree to a proposal for an immediate 30-day truce that emerged out of last week’s talks in Jeddah, Saudi Arabia.

While Ukrainian President Volodymyr Zelenskyy has accepted the proposal, Putin has yet to commit to the plan beyond saying he backs it in principle.

The Russian leader said last week that the plan would mostly benefit Kyiv as Russian forces were making gains and he had “serious questions” over the initiative.

Zelenskyy on Saturday accused Moscow of not wanting to end the conflict and seeking to “improve their situation on the battlefield” before agreeing to a ceasefire.

Russia has in recent weeks driven Ukrainian forces from most of its Kursk region, where Kyiv controlled an estimated 1,300sq km (500 square miles) of territory at the height of its incursion launched in August.