President Donald Trump said on Thursday that he believes Russian President Vladimir Putin will make a deal, and that the threat of sanctions against Russia likely played a role in Moscow seeking 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.

“He’s, he really, 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.

Earlier in the day, Putin said that the United States was making “sincere efforts” to end the war in Ukraine and suggested that 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 Zelenskyy, though he noted that a second meeting is not guaranteed.

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

The Kremlin warned on Thursday that it would be a big mistake to predict the outcome of the upcoming summit in Alaska involving Trump and Putin, the Interfax news agency reported.

Kremlin spokesman Dmitry Peskov said there were no plans to sign any documents following the summit on Friday in the Alaskan city Anchorage, according to Interfax.

Trump will go into talks with 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, US Secretary of State Marco Rubio said.

“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.”