MOSCOW - Mikhail Prokhorov, the owner of the New Jersey Nets basketball team and one of Russia's richest tycoons, said Monday he will run against Prime Minister Vladimir Putin in the March presidential election.

The colorful Prokhorov, who has a net worth estimated at $18 billion according to a report by NBC New York, could pose a serious challenge to Putin, whose authority has been dented by alleged widespread fraud during Russia's Dec. 4 parliamentary election.

 

Prokhorov, who is 46 and stands 6 feet 8 inches tall, made his fortune in investments and precious metals, NBC New York reported.

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He bought the New Jersey Nets in 2010 for a reported price of $200 million.

• Story: NBC New York: Nets Owner to Challenge Putin for Presidency

Putin's party only won about 50 percent of that vote, compared to 64 percent four years ago, and the fraud allegations have allowed opposition parties to successfully mount massive anti-Putin protests in Russia.

On Sunday, President Dmitry Medvedev promised on his Facebook page that the alleged vote fraud will be investigated. But Putin's spokesman, Dmitry Peskov, predicted Monday the probe will show that little vote fraud occurred and that it had no effect on the outcome of the ballot.

• Story: Facebook backlash for Medvedev over Russia election inquiry

That prediction signaled that Putin — who served as Russia's president in 2000-2008 and only became prime minister because of term limits — is holding firm, despite the protests, which have been the largest here since the 1991 collapse of the Soviet Union.

On Saturday tens of thousands of people in Moscow and smaller numbers in more than 60 other cities protested election fraud and called for an end to Putin's rule.

"The society is waking up," Prokhorov said at his news conference in Moscow.

He will have a good chance of appealing to Russia's growing opposition, which includes prosperous middle-class residents, many of whom are angered by Putin's bid to reclaim the presidency.

Asked whether he is going to join another opposition rally planned later this month in Moscow, Prokhorov wouldn't say, but he added that he agrees with many of the anti-Putin slogans that were shouted out during Saturday's protests.

Prokhorov's presidential bid follows his botched performance in the parliamentary race, when he formed a liberal party under tacit support of the Kremlin, then abandoned the project under what he called Kremlin pressure.

He has personally blamed Vladislav Surkov, a presidential deputy chief of staff, for staging a mutiny within the party's ranks. "I will solve that problem by becoming his boss," Prokhorov said Monday when he was asked whether Surkov could pose obstacles to his presidential bid.

NBC New York and the Associated Press contributed to this report.

Story update 11.30am ET/8.30am PT: The rallies staged in Russia over the weekend were a good sign for democracy, the White House said on Monday. "The demonstrations that occurred in Moscow and in many other Russian cities last Saturday represent a very positive sign to all those who support the democratic process," White House press secretary Jay Carney told reporters. "Russian government authorities allowed the demonstrations to take place, and refrained from interfering in them," he said.

MOSCOW - President Dmitry Medvedev was publicly denounced and insulted on his own Facebook page on Monday by thousands angry over alleged fraud in Russia's parliamentary election.

The Russian President ordered an investigation into claims the December 4 election, won by Prime Minister Vladimir Putin's United Russia party, was slanted in its favor. 

He announced the inquiry on Facebook (link in Russian) – the same site used by organizers of mass rallies in Moscow and St. Petersburg on Saturday – that called for the elections to be annulled and rerun. The protests were Russia's biggest opposition rallies since Putin rose to power in 1999.

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Within hours, Medvedev received one insult after another on the social media website from people who made clear his response to the demonstrations was insufficient.

NBC correspondent Stephanie Gosk said the majority of the 12,000 comments were negative – a remarkable act of open defiance in a country where political activists are jailed and hostility to the government would have been unusual only a few weeks ago.

One posted called Medvedev "a liar", while another told him: "Time to go".

• Story: Russia's Medvedev orders election investigation

Medvedev said: "I do not agree with any slogans or statements made at the rallies. Nevertheless, instructions have been given by me to check all information from polling stations regarding compliance with the legislation on elections," Medvedev said in his Facebook post.

"We don't believe you," replied Natalia Akhi.

Irina Arapova asked: "And who's going to do the checking? The executive authorities (United Russia)?"

The next big day of protests is planned on December 24 when Alexei Navalny, one of the protest leaders, will have served a 15-day jail term received for his role in a protest last week.

In yet another sign that the Russian leadership is under pressure, the governor of the Vologda region, Vyacheslav Pozgalev, resigned on Monday saying it was impossible to govern with the new level of public distrust.

Russian news agency RIA said Pozgalev – a Kremlin appointee and United Russia party member – wrote on his Twitter account: "I have filed a resignation petition to the president. I consider it impossible to run the region with such a level of distrust."

A pro-Putin demonstration is due to be held in Moscow later on Monday, while the next major opposition rally is already planned for December 24.

Anger over the election – which international monitors and the United States found fault with – unleashed years of pent-up frustration with Putin and his tight political controls. Frustration had mounted since September, when he announced plans to reclaim the presidency next year, opening up the possibility of him ruling until 2024.

State television and other channels broadcast footage of Saturday's big protest in Moscow, attended by tens of thousands, breaking a policy of showing almost no negative coverage of the authorities. However, the reports included no criticism of Putin.

Medvedev is a keen user of social media, according to the BBC. In addition to Facebook, he has Twitter accounts with 759,000 followers in Russian and 144,000 in English.

NBC News correspondent Stephanie Gosk and Reuters contributed to this report. 

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