"Unequivocally there is no damage," Sharon's personal physician, Dr. Bolek Goldman, said. "He had anti-coagulent treatment. He will need to be in the hospital for a few days."
Sharon never lost consciousness and his condition quickly improved, said Yuval Weiss, deputy director of the hospital. A decision would be made Monday on when to release the premier, a Sharon aide said on condition of anonymity because he was not authorized to speak on the issue.
"Initial checks showed he had a light stroke and during checks his condition improved. He was always conscious and didn't need any surgical intervention," Weiss said, adding that Sharon was speaking with his family.
Sharon, 77 and very overweight, has been a political fixture of Israeli politics for more than three decades. Last month he broke away from his hardline Likud Party and formed the centrist Kadima faction to contest March 28 parliamentary elections.
The nascent party, which has a commanding lead in the polls, is built around Sharon, and it was unclear what would happen if Sharon were too ill to campaign. If Sharon were incapacitated, Vice Premier Ehud Olmert, a close Sharon ally, would take over the government. The premier's illness would have little effect on Israeli policy or peace efforts, since no major decisions were expected during the campaign.
Sharon had just finished a meeting Sunday evening with government officials to discuss poverty when he felt weak, Israeli media reported. The premier was immediately rushed to the hospital in his official vehicle, all nearby roads were closed and he was brought directly to the emergency room, media reports said.
Sharon lost consciousness on the trip to the hospital, but quickly woke up, an aide to Sharon said on condition of anonymity because he was not authorized to speak to the media. A statement from the prime minister's office later denied he lost consciousness.
Israel TV said Sharon was a little confused, but conscious, and communicating with his doctors. He had no difficulty moving his arms and legs. He underwent an MRI exam and was being treated by neurologists, the station reported.
Shmuel Shapira, another hospital official, said Sharon was "in stable condition ... his condition is satisfactory."
Sharon's sons, Omri and Gilad, rushed to the hospital to be by his side.
Aides to Mahmoud Abbas called Sharon's office to check on his condition and to convey the Palestinian leader's wishes that he have a speedy recovery, officials in Abbas' office said, speaking on condition of anonymity because Abbas had not yet made an official statement.
Meanwhile, dozens of armed men from the Popular Resistance Committees, a small militant group, fired guns in the air and handed out sweets to motorists on the streets of Gaza City in celebration of the news that Sharon was ill.
Sharon, a former army general, was elected prime minister in 2001, months after the beginning of nearly five years of Israel-Palestinian violence. Sharon led the Israeli crackdown on the Palestinian uprising, and was vilified by many Palestinians. However, he also led Israel's pullout from the Gaza Strip last summer, after 38 years of occupation.
Following the Gaza pullout, Sharon threw the Israeli political map in disarray as he prepared to run for a third term in office in March 28 elections.
Sharon split from the Likud Party, which he helped found three decades ago, to form Kadima, saying that his old party had become too extreme. A group of hardline Likud lawmakers bitterly fought against Sharon's Gaza withdrawal plan. They lost the battle, but Sharon determined that he could no longer lead the party.
Polls show that Sharon's new party — which included more than a dozen former Likud lawmakers — would finish far ahead of other parties, all but guaranteeing he would form the next government and remain prime minister for a third term.
CBS News correspondent Robert Berger reports that at his age and health will now be a major factor. The ex-army general has never released his medical records but has insisted in recent years that he is not suffering from any serious ailments.