Sharon's severe illness in the middle of political campaigns – both in Israel and the Palestinian territories – will further complicate Middle East peacemaking efforts, reports CBS News correspondent David Hawkins.
Doctors said Sharon was to undergo a CT scan Friday morning to determine if the massive cranial bleeding that occupied surgeons for long hours after the stroke had completely stopped. Experts spoke of serious brain damage from the stroke and doubted he would recover.
Sharon's deputy,, immediately took the reins as acting prime minister and tried to convey a sense of stability, convening a Cabinet meeting Thursday morning. But Sharon's dramatic downturn left Israelis stunned and threw his ambitious peace agenda into doubt.
"I'm worried about the future of this country, about everything in this country," said Rafael Levy, a 42-year-old construction engineer from Tel Aviv.
60 Minutes correspondent Bob Simon says the mood in Tel Aviv is dismal.
"It's a nation in mourning. The radio is playing sad songs, television is non-stop coverage. It's mourning and it's shock, and it's very comparable to my mind to the death of [former Israeli Prime Minister Yitzhak] Rabin 10 years ago," Simon said.
Sharon's collapse less than three months before elections left his new centrist Kadima Party, which appeared headed for an easy victory, in limbo.
A poll conducted for Channel 10 TV and the Haaretz daily showed Kadima maintaining Sharon-like figures, far ahead of its main rivals, whether Olmert or two other Kadima notables head the party – but the expert who conducted the poll warned that its results must have been influenced by the shock at Sharon's condition, and the lead might evaporate.
Palestinians reacted with a mix of glee at seeing the fall of their longtime enemy and apprehension at the instability that could follow. Some Palestinian leaders worried that Sharon's illness could derail their Jan. 25 parliamentary elections. "We are watching with great worry at what might happen if he is harmed," Palestinian leader Mahmoud Abbas said. Abbas called Olmert on Thursday to express wishes for Sharon's recovery.
Some Palestinian children gave out sweets in the Gaza Strip at news of Sharon's illness.
Foreign leaders, who embraced Sharon following his unilateral pullout from the Gaza Strip last year, also expressed concern.
U.S. Secretary of State Condoleezza Rice praised Sharon as "a man of enormous courage," and British Foreign Secretary Jack Straw said he was praying for a miraculous recovery. Japanese Prime Minister Junichiro Koizumi postponed a visit to the region scheduled to begin Sunday, and two U.S. envoys who were to arrive Thursday delayed their trip.
Meanwhile, Christian broadcaster Pat Robertson suggested thatfor "dividing God's land."
Iranian President Mahmoud Ahmadinejad said he hoped for the death of Sharon, the latest anti-Israeli comment by a leader who has already provoked international criticism for suggesting that Israel be "wiped off the map."