Acting Mayor Vladimir Resin joined United Russia on Wednesday, getting the fast-track treatment a day after meeting with party leader and Prime Minister Vladimir Putin.
Resin's decision fueled speculation among analysts and bloggers that he was on the shortlist of candidates for mayor, which United Russia needs to submit to President Dmitry Medvedev on Saturday.
Resin, 74, served as first deputy mayor under Yury Luzhkov — who was ousted by Medvedev on Sept. 28 — and he was appointed acting mayor Sept. 29.
Before Tuesday's closed-door meeting with Putin, Resin was widely seen as an interim figure keeping the mayor's chair warm while the Kremlin decides on the next mayor.
Under United Russia's charter, an applicant has to wait six months to become a member, but Resin joined in a matter of hours. United Russia officials said Wednesday that this was made possible by the fact that Resin is a longtime supporter of the party.
Also Wednesday, Finance Minister Alexei Kudrin assailed Luzhkov and his management of Moscow's finances. Kudrin, a longtime critic of Luzhkov, said it would take years to solve the city's traffic problems because City Hall allocations for roads shrank from 26 percent of the city's budget in 2000 to just 4 percent last year.
Kudrin also criticized Luzhkov on Tuesday, saying one-fourth of his decrees have never been made public, despite laws that demand disclosure.
Separately, Oleg Mitvol, who was scandalously fired by Resin as prefect of Moscow's Northern Administrative District on Tuesday, said Wednesday that he would not contest the decision in court. "You understand that what is being done now will last for just a week," Mitvol told Interfax. "A new mayor will come, and everything will become clear then."
Crooner Iosif Kobson, a close Luzhkov ally and State Duma deputy, said the former mayor would leave Moscow for a weeklong vacation Thursday, RIA-Novosti reported.
The day before his dismissal, Luzhkov returned from a weeklong vacation in Austria where he was supposed to consider a Kremlin request to resign. Luzhkov on Tuesday started a new job as a department chairman at Moscow's International University, which is headed by Gavriil Popov, who served as mayor for two years before Luzhkov's 18-year reign began in 1992.