Updated

A spokesman at Hadassah Hospital said Tuesday there has been no change in Israeli Prime Minister Ariel Sharon's condition, and he remains in serious but stable condition in a coma.

Sharon briefly opened his eyes Monday in response to a recording of his grandson's voice, relatives told doctors, but hospital officials warned the movement may have been an involuntary twitch, and there were no signs that the comatose Israeli leader was any closer to regaining consciousness.

The 77-year-old prime minister has been unconscious in the hospital since suffering a massive stroke Jan. 4. Outside experts have said his failure to regain consciousness in recent days bodes poorly for his recovery.

After the stroke, Sharon underwent three operations to stop the bleeding in his brain. Medical officials said last week that he showed some movement on both sides of his body in response to pain stimuli, but he has shown no signs of improvement since then.

Sharon has been on a respirator, and he underwent a tracheotomy Sunday in which surgeons inserted a plastic tube in his windpipe to help him breathe. He has been taken off sedatives.