KIROV, Russia - Russian protest leader Alexei Navalny was convicted of stealing from a state timber company on Thursday, a verdict that could prevent him challenging Vladimir Putin for the presidency.

Russian protest leader Alexei Navalny (C) attends a court hearing trial in Kirov, July 18, 2013. Navalny was found guilty of theft on Thursday at a trial he says is politically motivated because of his opposition to President Vladimir Putin. Prosecutors have asked the court to jail Navalny for six years. The judge was expected to hand down a sentence later on Thursday at the trial in the industrial city of Kirov, 900 km (550 miles) northeast of Moscow. [Photo/Agencies]

Prosecutors have asked the court to jail Navalny for six years, a term that would keep him in prison until after the next presidential election in 2018. Judge Sergei Blinov was expected to hand down a sentence later on Thursday at the trial in the city of Kirov, 900 km (550 miles) northeast of Moscow.

Navalny, who emerged from rallies against Putin last year as the opposition's most dynamic leader, stood silent with a puzzled expression on his face as he was found guilty.

The tall and clean-cut anti-corruption campaigner, 37, then exchanged wry smiles with his wife, Yulia, who stood behind him in court. He sent tweets on his mobile phone while standing in front of the judge in a courtroom packed with journalists and opposition activists.

"The court, having examined the case, has established that Navalny organised a crime and ... the theft of property on a particularly large scale," the judge said, reading the verdict rapidly and without emotion.

On Twitter, Navalny said the judge was simply repeating the accusations made by prosecutors and agreeing with them. "So ... there will be no nice scenario with an acquittal," he tweeted.

Navalny says the charge - organising a scheme to steal at least 16 million roubles ($494,400) from a state timber firm when he was advising the Kirov region governor in 2009 - is politically motivated because of his opposition to Putin.

The crime carries a maximum sentence of 10 years.