A lawyer for Taisiya Osipova lodged on Thursday an appeal against the eight-year jail term handed down to the Russian opposition activist.

"I ask for the verdict to be acknowledged as unlawful and unfair, and be overturned," lawyer Svetlana Sidorkin said. "I also ask for the criminal case against Osipova to be closed."

Osipova was jailed on drug possession charges, which she denies.

Prosecutors have asked for her to be given four years in prison.

The 28-year-old was arrested in 2010 and imprisoned for ten years late last year after police found four grams of heroin at her home in the western Russian city of Smolensk. Osipova said the drugs were planted on her by officers after she refused to testify against her husband, Sergei Fomchenkov, a leader of the opposition Other Russia party.

Osipova is the mother of a five-year-old child and suffers from diabetes. Her sentence was overturned on appeal in February after then President Dmitry Medvedev called it "overly harsh," and called for a new probe. The court refused, however, to free Osipova on bail.