The US and Russian leaders are preparing to meet behind closed doors in Finland.
Donald Trump says he has "low expectations" ahead of talks with Vladimir Putin in Helsinki this morning.
He has also tweeted to say that America's relationship with Russia has never been worse.
Our relationship with Russia has NEVER been worse thanks to many years of U.S. foolishness and stupidity and now, the Rigged Witch Hunt!
— Donald J. Trump (@realDonaldTrump) July 16, 2018
While the two men have met before at larger summits, this is their first dedicated bilateral meeting.
Speaking to CBS News over the weekend, President Trump observed: "Nothing bad's going to come out of it, and maybe some good will come out.
"I go in with low expectations - I'm not going in with high expectations. I can't tell you what is going to happen."
The meeting comes amid continuing tensions between Russia and the West over issues such as Syria.
On Friday, 12 Russian intelligence officers were charged in the US with hacking offences connected with alleged interference in the 2016 presidential election.
Asked if he would ask Putin about bringing the Russian nationals to the US to face the charges, President Trump told CBS: "I hadn't thought of that. But certainly I'll be asking about it."