The Moscow election commission is to consider whether to disqualify protest leader Alexei Navalny from taking part in elections for city mayor on September 8, the Russian capital's election chief said Thursday.
The commission would meet "soon" to discuss violations in Navalny's campaign, Moscow election commission chief Valentin Gorbunov said.
"If the violations exceed the norms established by the law than the question will be raised of cancelling the registration of the candidate," Gorbunov said, according to comments confirmed by a spokesman to AFP.
The spokesman, declining to be identified, refused further details.
Navalny indicated he believed that the move had been taken as the authorities feared he could score embarrassingly well in the vote.
"Oi! The Moscow election commission announced that I could be removed from the polls," Navalny said in a message on Twitter. "Just when the run-off had become inevitable and SUDDENLY at that."
Pro-Kremlin Moscow mayor Sergei Sobyanin is widely expected to win the polls but Navalny has vowed to force the election into a second round.
The most prominent critic of President Vladimir Putin is standing as an independent candidate in the election, a poll he wants to use as a springboard to launch a nationwide campaign against the Russian strongman.
He was allowed to run for mayor in a surprise move after a court sentenced him to five years in prison last month for embezzlement in a disputed verdict.
He was arrested in the courtroom but then in a hugely unusual move released pending his appeal of the verdict in a move authorities said would allow him to campaign.
Earlier this month Russian prosecutors accused the 37-year-old father of two of breaking the law in his campaign by receiving donations from foreign nationals.
The charismatic lawyer who rose to fame during anti-Putin rallies that broke out in Moscow in winter 2011 denied the claim and said all funding for the September 8 polls was being gathered in strict accordance with the law.