Ailing thespian Soumitra Chatterjee has been put on life support system in Belle Vue Hospital in Kolkata.

"Nothing less than a miracle can save him," a doctor attending him said today.

"He is on different life support systems ... It seems that our almost 40 days' fight is not enough to make him well," the doctor said.

"Let's all pray so he gets better but it seems unlikely he will have a favourable outcome. We have informed all the family members and with a saddened heart they have accepted that nothing less than miracle can get him out of this situation," the doctor said in a bulletin.

Chatterjee, the doctor said, seems to not respond to the current therapies and "his situation is really grave and critical".

On Friday, the neurological condition of the 85-year-old actor deteriorated and an EEG had shown that there is very little activity in the brain, the doctor had said.

Chatterjee had undergone the first plasmapheresis on Thursday and tracheostomy on Wednesday so that he can breathe more easily.

He was admitted to the hospital on October 6 after testing positive for Covid-19. He later tested negative for the infection but Covid-19 encephalopathy set in and various other complications also surfaced.