"Of course, we will be ready to discuss everything, including problems that exist in the United States," Lavrov told reporters. He said Russia was monitoring the "persecution" of those behind the 6 January riot at the US Capitol.

"A lot of interesting things are happening there," he said, adding that Russia wanted to discuss "protection of opposition rights" in the United States.

The face-to-face summit meeting between Putin and Biden comes amid the biggest crisis in ties between the two countries since the end of the Cold War.

Ahead of parliamentary elections in September, Russian authorities are ramping up pressure on the already embattled opposition.

Putin's leading domestic opponent, Alexei Navalny, is in prison, serving two-and-a-half years in a penal colony on old fraud charges he says are politically motivated, and authorities are gearing up to outlaw his political network.

Tensions between US and Russia are also high over Ukraine and Belarus, which caused an uproar last week after authorities forced a European passenger plane to land in Minsk and arrested a dissident journalist.

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