Jailed Kremlin critic Alexei Navalny announced Tuesday that he is now working in the industrial sewing outfit of his penal colony after being ordered to take up prison labour.

Russian President Vladimir Putin's best-known domestic critic was imprisoned in February and is serving two-and-a-half years on old embezzlement charges in a penal colony around 100 kilometres (60 miles) east of Moscow.

Penal colonies, which are the most common form of incarceration in Russia, require inmates to choose from a variety of jobs.

"'Prisoner Navalny, your correction is impossible without involvement in labour activity,'" the politician quoted prison officials as telling him in a Facebook post run by his team. 

"'You have been with us for nine months -- it's time to work.'"

The 45-year-old opposition leader joked that he chose sewing over baking, although kitchen roles are considered more comfortable jobs. He said he wanted to avoid "nomenklatura" positions -- those reserved for officials in the Soviet era -- and be closer to the "masses".

Navalny last year survived a poisoning attack with Novichok nerve agent that he blames on the Kremlin, but which it denies. He was arrested in January after returning to Russia from Germany where he was treated.

Russia has since declared the anti-graft campaigner's organisations and nationwide network of political offices "extremist" and many of his top allies have fled the country.

Authorities have also launched a slew of new probes against him, including a new "extremism" investigation in September that could see him spend up to a decade more in jail.

In October, he was awarded the European Union's top human rights award, the Sakharov Prize for Freedom of Thought.