Russian protest leader Alexei Navalny on Thursday sent a car-load of complaints to court contesting the results of Moscow's mayor elections, as President Vladimir Putin was due to attend the inauguration of his ally as city supremo.
Incumbent mayor Sergei Sobyanin, who barely avoided a run-off in Sunday's closer-than-expected Moscow mayoral polls, will be sworn in during a ceremony attended by hundreds of guests led by Putin on Thursday evening, a Kremlin spokesman said.
The ceremonial swearing-in at one of the capital's landmark parks will take place after the Moscow election commission refused to conduct a partial vote recount demanded by Navalny, Sobyanin's main rival in the election.
Navalny said his team had put together documented evidence that the vote was partially rigged in favour of Sobyanin, who was appointed Moscow mayor in 2010 but had called the elections before his term was due to end.
According to official results, Sobyanin received 51.3 percent of the vote but Navalny's team insists that the inauguration should be cancelled because, according to its data, the mayor had polled around 49 percent.
Earlier Thursday, Navalny and his aides had brought some 20 boxes stuffed with what they say is documentary evidence of vote violations to the Moscow city court.
"We believe that the election on the whole should be cancelled because administrative resources have been used," Navalny told reporters, referring to government interference in the poll.
Similar complaints would be filed with district courts, Navalny's team said.
Navalny, who polled a stronger-than-projected 27.2 percent of the vote, insists that election officials helped the Kremlin ally avoid a second round run-off by allowing irregularities during at-home voting and at polling stations without observers.
The election commission has dismissed the claims and on Wednesday formally registered Sobyanin Moscow's mayor.
In a meeting with Sobyanin and other newly-elected regional chiefs, Putin praised the elections that took place in Moscow and elsewhere across Russia on Sunday.
"The legitimacy of these polls, their transparency, their accountability were on such a level which we have probably never before had in our country," he said.
Independent observers said however they had registered vote irregularities, although not as serious as those witnessed in previous polls.
Widespread claims of wholesale violations during 2011 parliamentary polls prompted tens of thousands to take to the streets of Moscow to protest against the ruling party United Russia and Putin himself.
Analysts say Navalny, who shot to prominence during those protests, was allowed to run in Moscow's mayoral vote to give it a veneer of legitimacy.
Few observers had expected him to poll so strongly, and nearly all pollsters had said he would gain around 20 percent of the vote.
In a departure from tradition, Sobyanin's swearing-in ceremony will take place in a museum at the Poklonnaya Gora War Memorial Park, one of the city's top landmarks.
"They need to cement this victory in a fast and ostentatious way," said pro-opposition political analyst Dmitry Oreshkin.
Vedomosti daily said election officials chose to ignore reports of violations after Putin said the elections were legitimate and transparent.
"The results of the brightest and most unpredictable political campaign of the past years -- Moscow mayoral polls -- were being prepared in an obscure, semi-secretive way," it said.
In the run-up to last year's presidential elections, authorities bussed thousands of people for a pro-Putin rally at the park at the peak of the anti-Kremlin demonstrations in the winter of 2011-12.
According to a notice posted on Navalny's blog, a major state company has been told to make sure its employees attend a concert in honour of Sobyanin's inauguration at the park.
Sobyanin's spokeswoman Gulnara Penkova denied that people were forced to attend the swearing-in en masse.
Analysts saw the election as a key breakthrough for Navalny but also as a sign of an alarming level of political apathy in Moscow, with turnout at just 32 percent.