Israeli Prime Minister Ariel Sharon opened his eyes twice today after family members played a tape of his grandson's voice, aides said.
This has raised hopes the 77-year-old may be emerging from a coma following his recent stroke.
But a spokeswoman for Hadassah hospital, where Mr Sharon has been treated since suffering a brain haemorrhage on January 4th, said relatives had observed "eyelid movements" whose medical significance was unclear.
"[Sharon's son] Gilad brought in a cassette with voice of Rotem, his eldest grandson, speaking to him, and he opened his eyes twice, each time for two or three minutes," one aide said.
"They believe it was so short because he is still fuzzy from anaesthesia yesterday," the aide said, referring to the tracheotomy, the insertion of a tube into Mr Sharon's windpipe to help him breathe, that surgeons performed yesterday.
"But the doctors didn't see it, so it is hard to determine whether it is serious or whether they are just getting their hopes up."
Doctors have been unsuccessful so far in rousing Mr Sharon since reducing, and later stopping, sedatives used to induce a coma aimed at stopping his brain from swelling.
In another sign Israel is moving quickly to fill the political vacuum left by Mr Sharon, his new Kadima party named interim Prime Minister Ehud Olmert as acting chairman to lead it into a March 28th general election.
US vice president Dick Cheney arrived in Egypt today at the start of a brief Middle East tour that will include visits to Saudi Arabia and Kuwait.
His meetings with Arab leaders are expected to focus on counterterrorism, the Palestinian election and energy.