JERUSALEM – Prime Minister Sharon started breathing on his own yesterday and moved his right arm and leg in response to pain stimulation in what his surgeon called an important development. But it will be days before doctors can determine whether he is lucid or will be able to return to the job.

“The prime minister is breathing spontaneously,” the director of Hadassah Hospital, Dr. Shlomo Mor-Yosef, said adding that the movements of Mr. Sharon’s arm and leg marked “a slight but significant improvement.”

Mr. Sharon’s response is a “very important” sign and indicated his brain stem is working, his chief surgeon, Dr. Felix Umansky, said briefing reporters for the first time.

It is still too early, however, to assess what impact the massive bleeding he suffered in his right brain would have on his abilities to think and reason or on the left side of his body, Dr. Umansky said.

“We are just at the beginning of a very long way,” the surgeon said. “It’s too early to talk about the cognitive issue.”

A final medical analysis on Mr. Sharon’s long-term prognosis would end days of uncertainty over the fate of the 77-year-old prime minister, heralded by many as the best hope for peace in the Middle East. Doctors said his chances of survival are better, but he is far from out of danger.

He remains hooked up to a respirator and unconscious in a guarded room where classical music is being played.

More clarity as to Mr. Sharon’s condition might enable his new, centrist Kadima Party to select a successor and start campaigning for March 28 elections. Acting Prime Minister Ehud Olmert – Mr. Sharon’s ally and a proponent of unilateral withdrawals from more Palestinian Arab-claimed lands – is seen as the most likely heir.

The Palestinian Arabs’ political future, which was to be decided in January 25 parliament elections, also appeared in limbo.

Palestinian leader Mahmoud Abbas reiterated yesterday that the vote would take place on time, but Palestinian Interior Minister Nasser Yousef that warned his security forces would not be able to protect polling stations against gunmen. Some have worried that gangs from Mr. Abbas’s Fatah Party may attack polling stations if Fatah appears to be losing to the Islamic terrorist Hamas party.

Mr. Sharon has been in a medically induced coma since his massive stroke January 4. Doctors plan to continue lowering the level of sedatives in his body over the next several days, Dr, Mor-Yosef said.

Mr. Sharon has not yet opened his eyes. His doctors hope he will when the sedative levels are lowered further.

Israel TV’s Channel 2 quoted Mr. Sharon’s advisers, who are keeping watch by his side, as saying he also responded to words in some fashion, though they weren’t specific.

Doctors had kept Mr. Sharon in an induced coma to help him recover from the stroke and brain surgeries, and Dr. Umansky said the doctors could put Mr. Sharon under again if his condition worsens.

The doctors’ final assessment on Mr. Sharon’s brain damage, whenever it comes, will be presented to Attorney General Meni Mazuz, who will decide whether to declare the prime minister permanently incapacitated.

In the event of such a ruling, the Cabinet would have to elect a prime minister within 24 hours, from among the five sitting Kadima Cabinet ministers who are also lawmakers, Justice Ministry spokesman Yaakov Galanti said.

Mr. Olmert, who is among the five, was named acting prime minister after Mr. Sharon’s stroke, and can serve in the role for 100 days, which would carry him through the elections.

The uncertainty over Mr. Sharon’s condition has unsettled Israelis, who have been anxiously following news updates. At the entrance to the hospital yesterday, three Jerusalemites hung up a white sheet with blue lettering in English and Hebrew that read,” Ariel Sharon, there is more to do, please wake up.”

In the Gaza Strip, where Sharon is reviled for his tough policies on Palestinians, 40 masked gunmen from the Al Aqsa Martyrs’ Brigades terrorist group held a demonstration against the Israeli prime minister.

Iran’s supreme leader, Ayatollah Ali Khamenei, said yesterday that Mr. Sharon’s death would be a serious defeat for American policy in the Middle East, state-run radio reported.

Amid uncertainty over Mr. Sharon, Secretary of State Rice was sending two envoys to the Middle East to try to resolve an Israeli-Palestinian dispute over the participation of Arab residents of Jerusalem in the Palestinian election.

Mr. Abbas has said such participation is a requisite for holding the election, and he said yesterday he had received American assurances Palestinian Arabs would be able to vote in the city, despite Israeli opposition.

Earlier yesterday, Israel allowed campaigning in Jerusalem, but said it has not yet decided whether to permit voting.