MINSK -- Belarussian opposition leader Alexander Kozulin, imprisoned since this spring's protests, is in critical condition after being on a hunger strike for more than 50 days, his wife said Friday.

In October, Kozulin began refusing solid food to try to draw attention to the authoritarian country's treatment of its opponents; since then, he has consumed only liquids.

Kozulin was arrested in March after leading a protest march following presidential elections in which he was one of four candidates. The elections, in which Alexander Lukashenko was declared the winner of a third term, were widely criticized in the West as undemocratic.

This summer, Kozulin was sentenced to 5 1/2 years in prison.

His wife, Irina, said she was allowed to speak with him by telephone Friday, the 50th day of his hunger strike.

"The condition of his health is critical; he can barely talk, and I am preparing for the worst," she said.

The Belarussian opposition's main figure, Alexander Milinkevich, has called on Kozulin to end the fast.

"Kozulin's death would be a useless catastrophe. He is [of] significantly more use to Belarus alive," Milinkevich said.