Navalny, 41, is a fierce opponent of President Vladimir Putin, who is widely expected to win re-election in March, extending his 17 years in power.

On Sunday Navalny, a veteran campaigner against corruption among Russia's elite, won the initial support of 742 people at a gathering in a district of Moscow, above the minimum 500 required to initiate a presidential bid.

"There is no large-scale support for Putin and his rule in this country," Navalny told the gathering, describing himself as a "real candidate" for the election and threatening a boycott of the vote by his supporters if he is barred from running.

But Navalny now needs to be officially registered as a candidate by Russia's central election commission, which has previously said he is ineligible due to a suspended prison sentence that he says was politically motivated.

Navalny has been jailed three times this year on charges of repeatedly organising public meetings and rallies in violation of existing laws. He says the Kremlin is deliberately trying to thwart his political ambitions.