The European Union says Sentsov, currently serving a 20-year prison sentence in Russia, is a symbol for all political prisoners held in Russia.

Ukrainian filmmaker Oleg Sentsov, who is serving a 20-year prison sentence in Russia after being accused of plotting acts of terrorism, will receive this year’s Sakharov Prize, the European Union’s highest human rights honor.

The EU said Sentsov, who earlier this month ended a protest hunger strike on its 145th day, is a symbol of all political prisoners held in Russia.

Antonio Tajani, president of the European Parliament, praised Sentsov’s “courage [and] determination,” announcing the award Thursday in Strasbourg, France. “We call upon the authorities to release him immediately,” he said.

In August 2015 Sentsov, a vocal opponent of Russia’s 2014 annexation of Ukraine’s Crimea region, was sentenced by a Russian court on terrorism charges. He vigorously denies the allegations.

On May 14 this year he went on hunger strike, demanding the release of Ukrainian political prisoners in Russia.

Senstov had hoped that international pressure would help secure their release, but Russia’s president Vladimir Putin ignored it. Feel-good headlines during this summer’s World Cup, hosted by Russia, largely drowned out the filmmaker’s message.

Senstov called off his hunger strike October 5 after losing more than 30 pounds (15kg) and following reports that his health had severely deteriorated and that he was suffering from heart, liver and kidney problems. Sentsov said he had not voluntarily ended the hunger strike but stopped only after being threatened with forced feeding by authorities. He is being held in a remote Siberian prison colony called “Polar Bear.”

Filmmakers and industry figures around the world and Hollywood stars including Johnny Depp and Patrick Stewart rallied to Sentsov’s cause. The European Film Academy and PEN America have led efforts to keep his case in the public eye.

The EU’s Sakharov Prize for Freedom of Thought, named after Soviet dissident Andrei Sakharov, was established in 1988 to honor those who defend human rights and freedoms. Past prize winners include South Africa’s first black president Nelson Mandela and Iranian director Jafar Panahi, who is living under house arrest in Tehran.

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

Campaigners are continuing to press for Sentsov’s release.

Mike Downey, deputy chair of the European Film Academy, told The Hollywood Reporter: “Oleg joins a long line of heroes and martyrs who have fought for all kinds of freedoms. Let’s hope that this is another step in the direction of his release and we shall be able to celebrate this great accolade with him in person sometime soon.”