Stanislav Klykh / Photo from svoboda.org

Tamara Klykh, the mother of the Kremlin's Ukrainian prisoner Stanislav Klykh, says her son has gone on hunger strike.

"This is what he has told her on the phone. Simply, it is no longer possible to stand: the cell is cold, the food is bad, he has constant nausea, and most importantly, it is abandonment!" Russian human rights activist Tatiana Shchur said on Facebook on May 24, citing her phone conversation with Tamara Klykh.

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According to the activist, Stanislav Klykh's hunger strike is a "call, a plea, a cry for help" addressed to the new president of Ukraine.

As UNIAN reported, the Ukrainian political prisoner was sentenced to 20 years in prison in the Russian Federation for allegedly participating in hostilities against Russian troops during the Chechen war in the winter of 1994-1995.

Klykh denies the charges and insists he has never been to Chechnya.

In 2017, the Ukrainian political prisoner underwent compulsory psychiatric treatment, as was decided by the heads of a Russian prison where he is being held.