Visiting Israeli Prime Minister Ariel Sharon (search) was heckled during a speech to Jewish leaders on Sunday, and about 1,500 demonstrators staged a noisy street protest against the Gaza disengagement plan he was defending.

Several protesters stood up during Sharon's speech, one shouting "Jews don't expel Jews." The prime minister had to pause when the interruption grew louder and the protesters were escorted out of the Baruch College (search) auditorium in Manhattan. He then received a warm ovation from the crowd.

Under Sharon's plan, Israel (search) will remove all 21 Jewish settlements in Gaza and withdraw from four small settlements in the West Bank beginning in mid-August.

"I said in the past, and I say it also today: I am willing to make painful compromises for peace," Sharon said. "I think that the entire world can now see how hard such compromises are. There is one thing on which we will not make any compromises — not now and not in the future — and that is our security."

Sharon's opponents accuse him of caving in to Palestinian violence and warn the moves will lead to further territorial concessions. Many protesters wore orange T-shirts Sunday, the color adopted by Gaza settlers who oppose his plan.

Security was tight for Sharon's visit, as police barricaded sidewalks to prevent protesters from getting too close to the auditorium. Chants of "Never again!" and "Let our people stay!" reached a crescendo when Sharon's motorcade passed through an intersection 100 yards away.

"To retreat in the face of terrorism is to invite more of it — not less," Rabbi Yosef Yitzchok Jacobson shouted during the street rally. "What have these Jews done to be thrown out? Why are they being expelled? Why not expel the terrorists?" he said.

Sharon arrived in New York for a three-day visit to the United States to bolster ties with American Jews, but also to discuss domestic issues like the plan to pull out of the Gaza Strip.

Palestinian leader Mahmoud Abbas "knows what he has to do," Sharon told reporters on his plane earlier Sunday. "There certainly has to be complete quiet. Without quiet, it will be impossible to move forward on the peace process."

In recent days, a flare-up of fighting in the Gaza Strip has left three Palestinian militants dead and militants fired rounds of mortar shells and rockets at Israeli communities.

Chief Palestinian negotiator Saeb Erakat said Sunday that Palestinians also want hostilities to end so that talks can progress.

"Both sides should exert an effort to achieve full quiet and once the Israeli guns are silent, we can assure that we will maintain the cessation of violence against Israelis anywhere," he said.

Abbas was scheduled to arrive in Washington on Tuesday and meet with President Bush on Thursday. He has said he would seek political and financial support from the United States.