A lawyer for Nadia Savchenko says the captured Ukrainian Air Force pilot is "dying slowly" in a Russian prison after more than 50 days on a hunger strike.

Ilya Novikov visited Savchenko at a hospital ward in Moscow's notorious Matrosskaya Tishina detention center on February 2.

He told RFE/RL's Current Time TV program on February 3 that Savchenko is still refusing to eat but was drinking about two liters of water a day while allowing doctors to inject "anything they deem necessary."

Novikov said: "To speak bluntly, she is dying, but she is dying slowly."

Savchenko was transferred to the ward on January 29 because of what medical personnel described as "abrupt weight loss."

Savchenko was captured by pro-Russian separatists in eastern Ukraine in June and transferred to Russian custody in July.

Russian prosecutors have charged her with involvement in the deaths of two Russian journalists who were killed while covering the war in eastern Ukraine.

They later charged Savchenko with illegally crossing the border into Russia.

Savchenko says the case against her is fabricated, her transfer to Russia was illegal, and that Russia has no right to prosecute her.