US President Donald Trump said on Thursday he believes Russian President Vladimir Putin will make a deal about his war on Ukraine, and that the threat of sanctions against Russia likely played a role in Moscow's decision to seek a meeting.

Trump is scheduled to meet with Putin in Alaska on Friday. The US president said he is unsure whether an immediate ceasefire can be achieved, but expressed interest in brokering a peace agreement.

"I believe now, he's convinced that he's going to make a deal. He's going to make a deal. I think he's going to, and we're going to find out," Trump said in an interview on Fox News Radio's "The Brian Kilmeade Show."

Earlier in the day, Putin said the United States was making "sincere efforts" to end the war in Ukraine and suggested Moscow and Washington could agree on a nuclear arms deal as part of a broader push to strengthen peace.

Trump also mentioned during the Fox interview that he has three locations in mind for a follow-up meeting with Putin and Ukraine's President Volodymyr Zelenskiy, though he noted that a second meeting is not guaranteed.

He said staying in Alaska for a three-way summit would be the easiest scenario.

"Depending on what happens with my meeting, I'm going to be calling up President Zelenskiy, and let's get him over to wherever we're going to meet," Trump said.

He said a second meeting, featuring Trump, Putin, and Zelenskiy, would likely dig deeper into boundary issues. Zelenskiy has been adamant about not ceding territory that Russian forces occupy.

"The second meeting is going to be very, very important, because that's going to be a meeting where they make a deal. And I don't want to use the word 'divvy things up,' but you know, to a certain extent, it's not a bad term, OK?" he said.

"But there will be a give and take as to boundaries, lands, etc, etc. The second meeting is going to be very, very very important. This meeting sets up like a chess game. This (first) meeting sets up a second meeting, but there is a 25% chance that this meeting will not be a successful meeting," he said.

He said it would be up to Putin and Zelenskiy to strike an agreement.

"I'm not going to negotiate their deal. I'm going to let them negotiate their deal," he said.

Halt to Ukraine fighting in Putin talks

Meanwhile, US Secretary of State Marco Rubio said President Donald Trump will go into talks with Russian President Vladimir Putin in Alaska on Friday hoping to achieve a halt to the fighting in Ukraine, but a comprehensive solution to the war will take longer.

"To achieve a peace, I think we all recognize that there'll have to be some conversation about security guarantees. There'll have to be some conversation about ... territorial disputes and claims, and what they're fighting over," Rubio told reporters at the State Department on Thursday.

"All these things will be part of a comprehensive thing. But I think the President's hope is to achieve some stoppage of fighting so that those conversations can happen."

Rubio said that the longer wars go on, the harder they are to end.

"And even as I speak ... there are changes happening in the battlefield which have an impact on what one side views as leverage or the other. So that's the reality of ongoing fighting, which is why a ceasefire is so critical," he said.

"But we'll see what's possible tomorrow. Let's see how the talks go. And we're hopeful. We want there to be a peace. We're going to do everything we can to achieve one, but ultimately it'll be up to Ukraine and Russia to agree to one."

Rubio said preparations for the meeting were going "very fast," as it had been put together very quickly.

He said he believed Trump had spoken by phone to Putin four times and "felt it was important to now speak to him in person and look him in the eye and figure out what was possible and what isn't."

"He sees an opportunity to talk about achieving peace. He's going to pursue it, and we'll know tomorrow at some point, as the President said, probably very early in that meeting, whether something is possible or not. We hope it is."