Imprisoned Ukrainian filmmaker Oleh Sentsov, a Crimean native who opposed Russia's 2014 takeover of the Ukrainian peninsula, has written in a letter to the Moscow-based Novaya Gazeta newspaper that he is not "going to give in."

"I do not expect good news [in 2019].... But it does not mean that I am going to give in, be disappointed, or regret anything," Sentsov wrote in a letter published on December 28, Radio Free Europe / Radio Liberty reported.

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Ahead of the New Year, Novaya Gazeta published letters penned by several people who were either sentenced, are facing trial, or are under investigation in high-profile cases in Russia that many call politically motivated.

Sentsov was sentenced to 20 years in prison after being convicted of terrorism in a trial criticized by human rights groups and Western governments as politically motivated.

The newspaper also published letters from Oyub Titiyev, an activist who is on trial in his native Chechnya, and Aleksei Malobrodsky, the former director of Moscow's Gogol Center.

Moreover, Novaya Gazeta published letters by three members of the so-called New Greatness movement: Ruslan Kostylenkov, who is in pretrial detention, and teenagers Maria Dubovik and Anna Pavlikova, who are under house arrest.