Prosecutors in Russia are asking a judge to extend the prison sentence of Kremlin opposition figure Alexei Navalny by another 13 years, the Moscow Times reported.

Navalny, who is serving a two-and-a-half-year prison sentence, is currently on trial for fraud and contempt of court, the outlet reported.

The prominent critic of Russian President Vladimir Putin recently spoke out against the country’s invasion of Ukraine, accusing the ruling party of using the war to distract Russian citizens from their problems at home.

“Thanks to Putin, hundreds of Ukrainians and Russian citizens may die now, and in the future, this number may reach tens of thousands,” Navalny said in a tweet. “Yes, he will not allow Ukraine to develop, he will drag it into the swamp, but Russia will pay the same price.”

Russian agents poisoned Navalny with a Soviet-era nerve agent in 2020, U.N. experts say, and he was arrested when he returned to the country in 2021 after receiving treatment in Germany.