Mikhail Khodorkovsky said Wednesday that he would run for the State Duma in a Moscow by-election expected to be held in December.

Ivan Starikov, a senior member of the liberal Union of Right Forces party, or SPS, said he and several politically diverse politicians on Wednesday created an initiative group to back Khodorkovsky's bid.

Khodorkovsky, the jailed billionaire who is appealing convictions on fraud and tax evasion, first expressed his interest in mounting a bid last month. Since then, he has received invitations to run for the Tomsk city legislature, the Novosibirk regional legislature and as Ulyanovsk mayor.

But Khodorkovsky said he had decided in favor of the State Duma, his press center said.

"I have to run in Moscow in order to have my words really heard in Russia and the world," he said in a statement.

Adopting a slightly sarcastic tone, he added that he had not been persuaded by the inexpensive but delicious food in the Duma cafeteria but by the chance to proclaim that "the current Kremlin regime has exhausted itself and its days are numbered."

Khodorkovsky intends to run for a seat in Moscow's single-mandate Universitetsky district that was vacated by liberal Deputy Mikhail Zadornov when he accepted the post as head of Vneshtorgbank's retail branch in June. The district, which is home to many students and university professors as well as affluent Muscovites, has a record of supporting liberals in elections.

The Central Elections Commission is expected on Friday to set the by-election for Dec. 4, commission chief Alexander Veshnyakov said Wednesday.

Starikov said the initiative group would represent Khodorkovsky before the Central Elections Commission and collect the signatures required for his registration. The group's members -- including liberal politician Irina Khakamada, National Bolshevik Party leader Eduard Limonov, senior Yabloko member and political analyst Andrei Piontkovsky, and former news anchor Sergei Dorenko of the Communist Party -- said in a statement that Khodorkovsky was "one of the brightest and most courageous opponents" of President Vladimir Putin's government, which they said was leading the country toward collapse.

Under the Constitution, Khodorkovsky has the right to run for office because his nine-year sentence will come into force only after all appeals are exhausted. The Moscow City Court is to begin considering Khodorkovsky's appeal to his May conviction on Sept. 14.

Khodorkovsky's lawyer Anton Drel predicted that the court would take only a few days to rule on the appeal, but Starikov said it would take at least a month.

If the vote is called for Dec. 4, registration will start on Sept. 19, Veshnyakov said. The district election commission is allowed to take up to 10 days to decide on whether to register a candidate.

If the court is still considering the appeal on Sept. 29 and Khodorkovsky's application is in order, the district commission will have to register his candidacy and announce it, said Arkady Lyubarev, a campaign expert with the Independent Institute of Elections.

Registration would allow Khodorkovsky to start campaigning, Communist Duma Deputy Viktor Ilyukhin said, Interfax reported.

However, if Khodorkovsky later loses his appeal, the district commission will be obliged to rescind his registration or annul his election as deputy, Veshnyakov said. "Everyone must know this so there are no incorrect political concoctions later," he said.

Sergei Ivanenko, the deputy head of the liberal Yabloko party, said that "the authorities have 1,000 ways to deny him registration, let alone stopping him from winning the election."

Duma Deputy Speaker Vyacheslav Volodin, of United Russia, said Khodorkovsky and his supporters were trying to restore "an oligarchic regime."

Starikov conceded that Khodorkovsky might not end up on the ballot but he said he could still win political capital by campaigning.

Khodorkovsky's trial and the $28 billion in tax bills that crushed his Yukos oil empire are widely seen as Kremlin punishment for his political and economic ambitions.