According to Israeli Radio early Tuesday, Sharon's condition was unchanged overnight.
Monday, media reports indicated that Prime Minister Ariel Sharon briefly opened his eyes for the first time since his stroke, but Hadassah Hospital in Jerusalem says only that the family reported seeing him move his eyelids and the significance of that is not clear.
In an interview with CBS News' Up To The Minute Contributor Frank Ucciardo, Dan Gillerman, Israel's Ambassador to the United Nations, said Israelis are very optimistic.
"We are all keeping our fingers crossed and praying and are very elated by every small, however minute, sign of progress," Gillerman said. "But I think there is still a very long way to go... And hopefully Sharon will survive and come back."
"This has been probably one of the most tragic events to hit Israel certainly since the assassination of Prime Minister Rabin," Gillerman added. "Sharon is not just a leader who is very respected, he's also a leader who is very much loved by the people."
Monday, the web site of the Yediot Ahronot newspaper reported Sharon opened his eyes twice. On one occasion, after a recording of a grandson's voice was played, the prime minister's eyes teared, he blinked, and then quickly opened his eyes, the site said. But they closed before doctors reached his room, the site added.
Dr. Anthony Rudd, a stroke specialist at St. Thomas' Hospital in London, said eye movement - including eye opening - is not a significant breakthrough.
"A coma is not an absolute all-or-nothing state. There are various stages," Rudd said. "His coma may be lightening a bit. It's not a dramatic breakthrough."
Given the length of the coma, "one still needs to be pessimistic," he said. "It means more if he opens his eyes in response to someone talking to him than it does if he simply opens them in response to strong stimulation or pain."
Sunday, Sharon underwent a tracheotomy to help wean him off the respirator that has been helping him breathe since his stroke.
The hospital says the surgery, conducted under general anesthesia, took less than an hour as doctors cut a small hole in Sharon's neck to insert a tube directly into his windpipe.
The hospital said that before the throat surgery, Sharon had a brain scan, which showed his condition was unchanged since the previous scan, carried out last Thursday.
Sharon was also taken off the last of the sedatives that were used to keep him in a medically induced coma, but he is still unconscious, according to the Sunday's statement from the hospital.
Outside experts said the tracheotomy was necessary because the plastic tube that had connected his windpipe with the respirator would have started to cause damage.