Russian billionaire Mikhail Prokhorov plans to run for president next year, he announced Monday.
Speaking at a press conference, Prokhorov described the decision to take on Vladimir Putin as "probably the most serious decision in my life," reported state news agency Ria Novosti.
The businessman, who Bloomberg describes as Russia's third-richest man, will stand as an independent candidate. He has not discussed his plans with Prime Minster Putin or President Dmitry Medvedev, he said.
Ria Novosti speculates that Prokhorov could joing forces with former finance minister and liberal Alexei Kudrin, who said in an interview published Monday that he had discussed forming a new political party with Prokhorov.
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Prokhorov will not run a negative campaign, he insisted, saying that "not more than 10 percent" of his platform would be based on criticism of Putin.
Prokhorov used to head the pro-business party Pravoye Delo—Right Cause—but quit in September after accusing the Kremlin of encouraging the party's members to rebel against him.
He accuses Putin's government of controlling every element of Russian politics, from which candidates run to how much media coverage they get.
GlobalPost's Fred Weir in Moscow said Prokhorov is a well-known figure in Russia:
For Russians, the towering tycoon (he's 6' 9") has long been in the headlines as the country's most eligible bachelor, an amateur athlete who posts high testosterone videos of his jet-ski stunts on YouTube, and an innovative entrepreneur who is developing an electric car to wean his countrymen from their addiction to internal combustion engines.
The metals tycoon and New Jersey Nets owner has an estimated fortune of $18 billion, according to the Forbes rich list.
He has to collect at least two million signatures backing his candidacy to be allowed to run, the Moscow Times said.
Ria Novosti noted that in a blog entry last week, Prokhorov claimed that many Russians did not vote in the latest parliamentary elections "because they think there is no one to vote for":
"But whether they like it or not, Putin is so far the only figure who can manage this inefficient state machine."
He also suggested that it should be made easier for candidates to stand for election, for example by reducing the number of signatures needed by 90 percent and allowing candidates to represent public organizations as well as parliamentary parties.
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