A Moscow court on Saturday upheld a ruling to jail the Kremlin’s most prominent opponent Alexei Navalny, sealing his first lengthy prison sentence in a decade of legal battles with Russian authorities.

Judge Dmitry Balashov dismissed Navalny’s appeal against a recent decision to imprison him for violating the terms of a suspended sentence on embezzlement charges.

The anti-corruption campaigner was ordered on February 2 to serve the time in a penal colony for breaching parole terms while in Germany recovering from a nerve agent poisoning he blames on the Kremlin.

Navalny appeared in court Saturday inside a glass cage for defendants, wearing a plaid shirt, smiling, waving and flashing the V for victory symbol.

In a closing address that referenced the Bible and Harry Potter, Navalny said he had no doubts about his decision to return to Russia.

“The Bible says: ‘Blessed are those who hunger for righteousness, for they will be satisfied,'” he told the court.

“I have no regrets that I am back… I am satisfied that in a difficult moment I did not break this commandment.”

Quoting from a character in Harry Potter, he said it was “important not to feel alone” because that was what the series’ villain Voldemort wanted.

He described the legal process to jail him as “absurd” and called on Russians to take action to make the country a better place.

“Russia should be not only free, but also happy,” Navalny said.

Prosecutors lashed out at Navalny, saying he acted as if he was above the law and had “an exclusive right to do as he pleases”.

The judge on Saturday decided to count six weeks Navalny was under house arrest as part of the time served, so he will now be imprisoned for just over two-and-a-half years in a penal colony.

The ruling to sideline one of the most prominent players in Russian political life came just hours before Navalny was due in court again.

Prosecutors in a separate trial have called for him to be fined the equivalent of $13,000 for calling a World War II veteran a “traitor” on Twitter last year, with a verdict also expected Saturday.

They also asked for Navalny to be jailed on the same 2014 fraud conviction because the tweet was posted while he was serving the suspended sentence.

Supporters of the outspoken opposition figure say the cases against the 44-year-old are a pretext to silence his corruption exposes and quash his political ambitions.

– Western pressure for release –

The 94-year-old veteran at the centre of the defamation trial appeared in a video that Navalny derided for promoting constitutional reforms, passed last year, that could allow President Vladimir Putin to stay in power until 2036.

A series of theatrical hearings in the case ended Tuesday with Navalny asking if the judge could recommend a recipe for pickles, since it is “pointless to talk about the law” with her.

Russia has come under increasing Western pressure to release Navalny since he was detained on arrival at a Moscow airport in January.

He had spent months recovering in Germany from the attack with Novichok that he blames on the Kremlin. Russia has repeatedly denied involvement.

The arrest sparked large protests across the country that saw more than 10,000 people detained, while the European Union threatened to impose new sanctions on Moscow.

Europe’s rights court ruled this week that Russia must immediately release Navalny, a motion swiftly brushed aside by the justice ministry.

Navalny’s jailing has exacerbated a crisis in Moscow’s ties with the West that began with the annexation of Crimea from Ukraine in 2014.

EU foreign ministers, who are considering fresh sanctions, are due to meet with two top Navalny aides in Brussels on Sunday. (AFP)

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