The most vocal Kremlin critic in Russia's presidential contest was barred from the ballot Sunday by election authorities who said tens of thousands of signatures on his nominating petitions were faked.
The denial of registration to former Prime Minister Mikhail Kasyanov will likely fuel criticism of the election as undemocratic and stage-managed by the Kremlin.
Opinion polls gave Kasyanov little chance of posing a significant challenge to President Vladimir Putin's hand-picked successor, Dmitry Medvedev, in the presidential election. However, he could have been an embarrassment for Putin and Medvedev because of his harsh criticism of the Kremlin.
Kasyanov's spokeswoman, Yelena Dikun, denounced the election officials' decision as politically motivated. "The authorities are afraid of a strong competitor, they are afraid that he would speak out and tell the truth," Dikun told The Associated Press.
The Central Election Commission ruled that Kasyanov should be kept off the ballot in the March 2 vote because more than 13 percent of signatures in two large samples checked were counterfeit.
Commission member Elvira Yermakova told the commission that more than 80,000 signatures were found to be bogus during the check. She also pointed to other flaws in Kasyanov's documents submitted for registration.
Presidential aspirants not affiliated with political parties must submit 2 million signatures supporting their bid to get on the ballot. Kasyanov's campaign said it turned in 2,067,000 signatures.
The election officials' check left Kasyanov with less than 2 million valid signatures. By law, registration can also be denied if more than 5 percent of an aspirant's signatures are found to be invalid.
The Prosecutor General's office has already opened a forgery case against the campaign of Kasyanov, who was Putin's first prime minister but became a critic after his dismissal in 2004.
Kasyanov has rejected the election officials' claim about forged signatures as "simple propaganda." He said earlier this week that if he were kept off the ballot, Putin would be to blame. "It's not up to the Central Election Commission, it's up to Vladimir Putin," he said.
Medvedev faces no strong challengers, and other liberal Putin foes who sought to mount campaigns, including chess great Garry Kasparov, have accused the Kremlin of forcing them out of the race.
Medvedev's approval ratings soared after Putin named him as his preferred successor last month, boosted by positive coverage by national television stations, all controlled by the Kremlin. The latest opinion poll, released this week by the Levada Center, had about 80 percent of respondents saying they would vote for Medvedev.