TBILISI: Georgia's opposition leader and ex-president Mikheil Saakashvili returned to prison from a military hospital on Thursday after recovering from a hunger strike protesting his jailing.

Saakashvili had refused food for 50 days until late last month following his incarceration on an abuse of office conviction he has denounced as politically motivated.

The 54-year-old pro-Western reformer called off the hunger strike after he was placed -- in a critical condition -- in a military hospital in Georgia's eastern city of Gori.

"Convict Mikheil Saakashvili is in the 12th penitentiary establishment," the prison service said on Thursday, referring to a jail in the town of Rustavi about 30 kilometres (20 miles) from capital Tbilisi.

A lawmaker for the ruling Georgian Dream party, David Sergeyenko, told reporters that military hospital doctors said Saakashvili's health had "stabilised".

Saakashvili's doctors, who examined him in custody, said this month he had developed a number of neurological diseases "as a result of torture, ill-treatment, inadequate medical care, and a prolonged hunger strike".

They said he had been diagnosed with the potentially life-threatening brain disease Wernicke encephalopathy and with post-traumatic stress disorder (PTSD), among other conditions.

Georgia's president from 2004 to 2013, Saakashvili was arrested in October, shortly after he secretly returned to Georgia from exile in Ukraine.

His exacerbated a political crisis stemming from a parliamentary vote last year that the opposition denounced as fraudulent and spurred the largest anti-government protests in a decade.

Rights groups have accused the Georgian government of using criminal prosecutions to punish political opponents and critical media.