MOSCOW (AP) — The lawyer for an imprisoned Ukrainian filmmaker who has been on a hunger strike for 120 days says his health has suffered irreversible damage.

Oleg Sentsov, an opponent of Russia's 2014 annexation of Crimea, was sentenced to 20 years in prison in 2015 for conspiracy to conduct terror attacks, charges that he denies. He has refused to seek a pardon from Russian President Vladimir Putin.

Sentsov's lawyer, Dmitry Dinze, said Monday that his condition has steadily worsened, resulting in "irreversible changes affecting the cardiovascular system, kidneys and liver." He added that Sentsov is increasingly frail and finds it difficult to get up from his bed.

Prison officials said Sentsov was being given a nutritious formula daily.

Sentsov's case has drawn close international attention, with Western nations campaigning for his release.