Prison doctors will have a meeting due to the refusal of food by Ukrainian pilot Nadia Savchenko, who is under arrest on suspicion of complicity in the murder of Russian journalists, Kristina Belousova, an official with the Federal Penitentiary service (FSIN), said.

"Savchenko has refused to eat for three days. For that reason a board of doctors will meet today," Belousova told Interfax on Monday.

Belousova said Savchenko is under constant medical observation "and will be transferred to a civilian medical establishment if need be."

Mikhail Fedotov, the head of the Russian presidential human rights council, said after visiting Savchenko in the detention facility earlier on Monday that Savchenko had resumed her hunger strike and may be hospitalized due to her deteriorating condition.

"From the conversation with her, it seems that everything is OK, but objective indicators cause serious suspicions: she has lost eight kilos in one week, her low blood sugar levels cause a lot of concern and some other test results are alarming," Fedotov said.

"She is not eating anything, she only drinks, she is not limiting her water intake. Her transfer to a civilian hospital is being discussed," he said.

Fedotov said Savchenko is currently under prison doctors' observation and they will decide whether she should be transferred to hospital. "Her transfer to hospital is possible this week," he said.

Fedotov said Savchenko's transfer to a civilian hospital may create problems with visitation by Public Observer Commission and lawyers.