Ukrainian filmmaker Oleg Sentsov is in a "catastrophically bad" state and could be close to death after hunger striking in a Russian jail for nearly three months, his cousin said Wednesday.
Sentsov's cousin Natalya Kaplan wrote on Facebook that she received a letter from Sentsov through a lawyer who visited him yesterday.
"Things aren't just bad, they're catastrophically bad," Kaplan wrote.
"He wrote that the end is near -- and he wasn't talking about his release," she said, suggesting he believes he is close to death.
Sentsov launched a hunger strike in May ahead of the World Cup, calling for hosts Russia to free all its Ukrainian political prisoners, and has vowed to keep going to the end.
Sentsov's lawyer Dmitry Dinze on Tuesday told AFP that the prisoner has lost 30 kilogrammes from his original weight of 100 kilogrammes, his heart rate has slowed and he has very low levels of red blood cells.
He is being sustained with water and a drip with glucose and vitamins.
Ukrainian foreign ministry spokeswoman Mariana Betsa on Wednesday wrote on Facebook that Kiev had received "concerning information about the deterioration of Sentsov's health."
"We call on our partners to step up pressure on Russia to free Sentsov," she said.
Dinze posted on Facebook a handwritten note from Sentsov where he stressed his intention to continue, saying: "I'm not ill, I'm on hunger strike, and I don't plan to stop."
In the note, he said his condition meant he was not transportable to a hospital in his home region as he might not arrive alive.
The 42-year-old is serving a 20-year sentence in the far north of Russia after being convicted three years ago of arson attacks in his native Crimea following its annexation by Moscow.
Ukrainian President Petro Poroshenko and Russia's Vladimir Putin discussed the possibility of a prisoner swap and Sentsov's mother appealed to Putin to pardon her son but supporters are losing hope that he will ever be released.
According to Kiev's estimates, Russia is currently holding around 70 Ukrainian political prisoners.
As a filmmaker Sentsov is best known for his film "Gamer", which was screened at the Rotterdam Film Festival in 2012. Stars including Pedro Almodovar and Johnny Depp have appealed to Russia for his release.