Jailed opposition leader Alexei Navalny expressed hope for a better future in Russia as his supporters picketed and demonstrated to mark his 47th birthday on Sunday.

Navalny is serving a nine-year sentence for fraud and contempt of court, charges he says were fabricated to punish him for his work exposing official corruption and organizing protests against the Kremlin.

He faces a new trial on extremism charges that could keep him in prison for decades. Kremlin critics see the case as another attempt by the Russian government to isolate President Vladimir Putin’s most prominent foe.

Navalny’s associates called rallies to show their support in Russia and abroad on Sunday.

Risking their own prison terms, some Navalny supporters in Russia celebrated his birthday by holding individual pickets, while others painted graffiti. Police quickly detained many for questioning, and officers maintained a heightened presence in central Moscow.

Pro-Navalny demonstrations were held in various European cities.

Navalny said in a social media post released by his allies that he would obviously prefer to spend his birthday with a family breakfast, kisses from his children and gifts, but «life is such that social progress and a better future can only be achieved if a certain number of people are willing to pay for the right to have beliefs”.

“The more people there are, the lower the price each has to pay,” he said. «And there will certainly come a day when it will be routine and not dangerous at all to tell the truth and uphold justice in Russia.»

Navalny was arrested in January 2021 upon returning to Moscow after recovering in Germany from a nerve agent poisoning that he blamed on the Kremlin.

He initially received a two and a half year prison sentence for a probation violation. Last year, he was sentenced to nine years for fraud and contempt of court. He is currently serving time in a maximum security prison 250 kilometers (150 miles) east of Moscow.

The extremism charges against Navalny, which could keep him in prison for 30 years, relate to the activities of his anti-corruption foundation and statements by his top associates. His allies said the charges retroactively criminalize all activities of Navalny’s foundation since its creation in 2011.

The new accusations come as Russian authorities intensify their crackdown on dissent amid fighting in Ukraine, which Navalny has strongly criticized.

A Moscow court scheduled a preliminary hearing on Tuesday to discuss technical issues related to a new trial of Navalny, rejecting a request by his lawyers for more time to examine voluminous new charges that it dismissed as «absurd.»

Navalny also quoted an investigator who told him he would also face a separate military court trial on terrorism charges that potentially carry a life sentence.

He said in a social media post Sunday that he sees his prison term as «just an unpleasant part of my favorite job» and thanked his supporters.

“My plan for the previous year was not to become brutal and bitter and not to lose the indifference of behavior; this is where defeat begins,” he wrote. «And if I was successful, it was only thanks to your support.»