A Russian court sentenced an ally of jailed Kremlin critic Alexei Navalny on Friday to nine and a half years in prison for running an "extremist organisation", her legal team said, Paralel.Az reports citing Reuters.

Ksenia Fadeyeva has served as a local lawmaker since 2020 in the Siberian city of Tomsk and is also a former head of Navalny's anti-corruption organisation in the surrounding region.

Russian authorities designated Navalny's organisation "extremist" in 2021, effectively banning it and imposing harsh penalties on those involved in its previous legal activities.

In a statement published on the messaging app Telegram, a group representing Fadeyeva's allies said she would appeal the sentence.

Fadeyeva had previously been banned from using the Internet since Dec. 2021, and has been under house arrest since October.

In 2020, Fadeyeva was one of two pro-Navalny candidates who won election to the municipal council in the Siberian university city of Tomsk, a rare success for an opposition movement that Russian authorities had largely barred from contesting elections.

During Fadeyeva's leadership of the local Navalny organisation, Tomsk became a relative stronghold for the movement, with the city of 580,000 electing an opposition-heavy city council.

Navalny himself, who rose to prominence by lampooning President Vladimir Putin's elite and alleging vast corruption, is serving prison sentences totalling more than 30 years on a series of charges that he says were trumped up to silence him.

He was transferred this month to a penal colony north of the Arctic Circle. His lawyer said Russian authorities wanted to isolate Navalny ahead of Russia's March presidential election. As a prisoner, Navalny is unable to run in elections.

His supporters, many of whom have fled abroad in recent years, cast Navalny, 47, as a future leader of Russia, though it is unclear how much popular support he has.

The authorities view him and his supporters as extremists with links to the CIA intelligence agency who they say is seeking to destabilise Russia.