BRUSSELS (AP) — The European Union on Thursday awarded its top human rights prize to Oleg Sentsov, a Ukrainian filmmaker imprisoned in Russia accused of plotting acts of terrorism, calling him a symbol of all political prisoners being held there.

Sentsov was sentenced to 20 years in prison in 2015 for conspiring to commit acts of terrorism, charges he denies. He has been one of the most vocal opponents of Russia's annexation in 2014 of his native Crimea region of Ukraine. The 42-year-old director staged a hunger strike for 144 days to protest the incarceration of dozens of Ukrainians in Russia. He ended it earlier this month, faced with the prospect of being force-fed.

European Parliament President Antonio Tajani, announcing the decision in Strasbourg, France, said that Sentsov was awarded the Sakharov Prize "because of his courage, his determination."

"We call upon the authorities to release him immediately," Tajani said, adding that this is urgent due to Sentsov's poor health since the hunger strike.

The parliament's rapporteur on Ukraine, Michael Gahler, noted that throughout his time in jail "Sentsov has not demanded his own release. He has become the voice of around 70 other innocent individuals perishing in inhumane conditions in Russian jails scattered around the vast country."

"By awarding him this prize, we are bearing testimony to the fact that they are not forgotten," Gahler added.

Liberal group leader Guy Verhofstadt welcomed the decision and said he hopes it "will help Sentsov and all Ukrainians arrested or convicted in Russia on politically-motivated grounds to be free again and able to return to their home country."

Sentsov has described his prosecution as a political vendetta. Prominent political and cultural figures around the world have campaigned for his release.

On Tuesday, Poland bestowed its eighth annual Pro Dignitate Humana (For Human Dignity) award on Sentsov, saying that his activity "deserves the highest respect."

The EU award, named after Soviet dissident Andrei Sakharov, was created in 1988 to honor individuals or groups who defend human rights and fundamental freedoms.

A group of non-governmental organizations saving migrants in the Mediterranean Sea and Moroccan political activist Nasser Zefzafi were shortlisted with Sentsov as finalists.

The prize will be presented in a ceremony in Strasbourg on Dec. 12.