Prime Minister Ariel Sharon left the hospital Tuesday, saying he is in a hurry and fit enough to get back to work after suffering a mild stroke, but aides suggested the rotund 77-year-old may not follow doctors' orders to go on a diet.

Sharon returned to the fray just hours after his bitter rival, Benjamin Netanyahu, won the race to replace him as head of the battered Likud Party. Sharon quit the hard-line Likud last month because it resisted his plan to move forward on a peace deal with the Palestinians.

Sharon's illness raised questions about his ability to lead his new party, Kadima, into March elections, and then lead the country if elected to a third term. On Tuesday, the prime minister shrugged off those concerns.

"Now I have to rush back to work," he told reporters as he left Jerusalem's Hadassah Hospital.

Asked if the stroke affected his performance, Sharon replied, "I don't think it will affect my functioning."

Sharon was rushed to Hadassah on Sunday evening and had not been seen or heard publicly since he was hospitalized. Doctors at Hadassah said the stroke briefly affected his speech but did not impair his memory or cognitive abilities, or leave permanent damage.

Hadassah official Shlomo Mor-Yosef said there were no major restrictions on Sharon's activities.

"He obviously could lose some weight, like many people," Mor-Yosef said of the minister. "He should scale back his activities. We recommend that he gradually resume his regular schedule over the next few days."

Doctors say Sharon is generally in good health, but they have been advising him to lose weight since 1965. Aides will not disclose Sharon's weight.

"The prime minister is a man who already has a few years behind him. He has certain habits that I think are difficult to change," Cabinet Secretary Yisrael Maimon told Israel's Army Radio. "Regarding the culinary issues, maybe it's more difficult, but we will all pitch in."

Sharon spokesman Asaf Shariv said aides have not broached the subject of dieting with the prime minister during his hospital stay, and the prime minister had not brought it up, either.

The prime minister, who is about 5-foot-7, often jokes about his love of food and his girth. His favorite food is "meat in every way," Shariv said.

A day before suffering the stroke, Sharon enjoyed a typical meal with a close circle of family and friends: hamburgers, steak in chimichurri sauce, lamb chops, shish kebab and an array of salads, the Israeli daily Maariv reported.

For dessert, Sharon had chocolate cake.

New polls Tuesday showed Sharon — Israel's most popular politician — gaining ground after his stroke, with Likud still languishing. If poll trends hold, Kadima would be able to form a moderate coalition following the March balloting, and a Netanyahu-led Likud would head a right-wing opposition.

A survey by the Dahaf Research Institute published Tuesday gave Kadima 39 of parliament's 120 seats, or one more than in a survey last week. Ninety-one percent of those questioned said Sharon's stroke would not influence their vote.

Likud, which captured 40 seats in 2003 elections under Sharon, captured 13 seats, compared with 11 in the previous poll. The dovish Labor Party lost two seats, winning 21 — the same number it has now.

The survey of 580 people was taken Monday — a day after Sharon's stroke and the same day Likud held its leadership race. The poll had a margin of error of 4.5 percentage points.

Sharon's exit from the Likud left behind a small group of lawmakers, including Netanyahu, who opposed his Gaza Strip withdrawal and object to further territorial concessions to the Palestinians.

Netanyahu, a former prime minister, captured 44 percent of the vote in Monday's Likud primary, compared with 33 percent for Foreign Minister Silvan Shalom. Two hard-line candidates divided the remaining votes.

Netanyahu, who quit Sharon's Cabinet in protest just before the Gaza pullout, told cheering backers his victory was the beginning of "returning the Likud to power."

"The country is facing difficult challenges, and I don't think it's headed in the right direction," Netanyahu said in a crowded room in party headquarters.

"First of all, we must bring the Likud back to itself and then to the leadership of the country. It begins now, up, up and up."

Netanyahu, 56, a forceful public speaker who served as prime minister in 1996-1999, is Sharon's bitterest rival and could be a formidable candidate, leading an attack on Sharon from the hawkish side, while the dovish Labor Party chips away at the other flank.

Had Shalom, a moderate, won the Likud leadership race, the party would have been more likely to ally with Sharon in a coalition government.

The Likud primary fills out a picture of Israel's political scene, which was scrambled by Sharon's decision to leave Likud four weeks ago and labor union chief Amir Peretz's surprise win of the Labor Party chairmanship, beating veteran Israeli statesman Shimon Peres.

In the West Bank town of Bethlehem, about two dozen gunmen briefly seized Bethlehem's city hall on Manger Square and near the Church of the Nativity, demanding jobs in the Palestinian security forces.

Hundreds of Palestinian police and onlookers rushed to Manger Square after the gunmen appeared on the roof of city hall, pointing their weapons toward the crowd. Police sealed the streets leading to Manger Square.

After about an hour, the gunmen, who have ties to the ruling Fatah movement, met with the governor of Bethlehem and then walked out of the building. It was not immediately clear how the standoff was resolved.

The incident took place just four days before Christmas. The Church of the Nativity, one of Christianity's holiest shrines, stands over the grotto where tradition says Jesus was born.