A meeting between Russian President Vladimir Putin and his U.S. counterpart Joe Biden in Geneva on Wednesday is unlikely to yield concrete deals but the talks will still be useful, a Kremlin aide said.

The leaders will meet for the first time since Biden became president as the bilateral relationship stands at the lowest point in years.

Putin's foreign policy adviser, Yuri Ushakov, told reporters that the agenda - apart form the final communiques - was confirmed in his phone call with White House national security adviser Jake Sullivan on Monday.

Nuclear stability, climate change, cybersecurity and the fate of U.S. and Russian nationals who are in prison in each other's countries would be on the agenda, the Kremlin aide said.

"I'm not sure that any agreements will be reached. I look at this meeting with practical optimism," Ushakov told reporters in comments cleared for publication on Tuesday.

Biden, who called former KGB operative Putin a killer in March, has cast Russia as engaging in unacceptable behaviour on a range of fronts. He has also talked about Russia's "dilemmas" - its post-Soviet economic collapse, what he called overreach in Syria and problems with COVID-19.

In phone call in April, Biden proposed a summit with Putin to tackle their disputes.

Russia-U.S. ties slumped to a post-Cold War low following Russia's annexation of Ukraine in 2014. Washington also accused Moscow of interference in the 2016 presidential elections, imposing sanctions on Russian companies and individuals.

"The situation is just close to critical. Of course, something should be done in this context," said Ushakov, who was the Russian ambassador to the United States from 1998 to 2008.

The leaders have separately opened the door to a possible exchange of prisoners -- two former U.S. Marines held in Russia for Russians in U.S. prisons. A lawyer said last year that Russian arms dealer, Viktor Bout, was one of the prisoners Moscow wants freed.