Georgia's jailed opposition leader and ex-president Mikheil Saakashvili, who has been on hunger strike for weeks, is in critical condition and lacks proper medical care, doctors said Wednesday.

Saakashvili, president between 2004 and 2013, has been refusing food for 48 days to protest his imprisonment on Oct. 1, shortly after returning from exile in Ukraine.

Georgia's government has refused to move him from the prison hospital to a civilian clinic, against the advice of doctors who have warned of the risk to Saakashvili's life.

On Wednesday, a council of medics set up by ombudsperson Nino Lomjaria said after examining Saakashvili that his "current status is assessed as critical" and that he faced a risk of fatal complications in the "immediate future."

The prison hospital, where Saakashvili is being treated, fails to meet his medical needs, they added, calling for his immediate transfer to intensive care in a civilian clinic better equipped to care for him.

Last week, Saakashvili was taken to a prison hospital where, Amnesty International said, he had been "denied dignity" as well as adequate care.

The rights group on Twitter described it as "selective justice" and "apparent political revenge."The 53-year-old pro-Western reformer has said prison guards assaulted him and that he fears for his life.

The United States State Department has urged the Georgian government to "treat Mr. Saakashvili fairly and with dignity."

Several opposition lawmakers have also been on hunger strike for days, demanding proper medical care for Saakashvili, a call reiterated by the U.S. and the European Court of Human Rights. Georgia must take steps "to inform the Court about the applicant's current state of health, to ensure his safety in prison, and to provide him with appropriate medical care for the post-hunger-strike recovery period," the ECtHR said last week. It also urged Saakashvili to "call off his hunger strike."

On Tuesday, Justice Minister Rati Bregadze ruled out Saakashvili's transfer to a civilian clinic, insisting "there had been no single instance of Saakashvili not receiving a medical service he required."Saakashvili said last week he had decided to end the hunger strike if he was transferred to a civilian "high-tech clinic for post hunger strike rehabilitation."

Last year, Saakashvili's arrest exacerbated a political crisis stemming from parliamentary polls that the opposition denounced as fraudulent.

It has also led to some of the largest anti-government protests in a decade. Prime Minister Irakli Garibashvili sparked a debate recently, saying Saakashvili "has the right to commit suicide" and that the government had been forced to arrest him because he refused to quit politics.