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Prime Minister Ariel Sharon (search) threatened to dismiss Cabinet ministers who don't support his plan to withdraw from the Gaza Strip (search), participants in Sunday's meeting said, raising the stakes in a showdown that could break up the government.

During a heated Cabinet debate, Sharon told the ministers that he is determined to get his plan approved even if he has to "change the makeup of the government or take unprecedented political steps," one of those present said on condition of anonymity.

The meeting broke up Sunday afternoon without a decision.

Ministers said that efforts were under way to reach a compromise between Sharon and his main adversary, Finance Minister Benjamin Netanyahu. A vote isn't expected before next week.

The debate came hours after an Israeli missile strike killed a senior Hamas commander and two other Palestinians in Gaza. The Israeli military has stepped up a crackdown on Palestinian militants ahead of a possible withdrawal to avoid any appearance that it is fleeing under fire.

The Gaza withdrawal proposal has bitterly divided Sharon's 23-member Cabinet, with 11 ministers having spoken in favor of a Gaza withdrawal and 12 against.

Israeli media reported that two ministers from the hard-line National Union party — Transportation Minister Avigdor Lieberman and Tourism Minister Benny Elon — could be the first to go, which would give Sharon the one-vote majority he needs.

Sharon's Likud Party (search) rejected his Gaza pullout plan in a referendum on May 2, but the prime minister has pledged to push forward.

After failing to reach a compromise with hard-line Cabinet members last week, Sharon decided to present a plan with only minor changes on Sunday.

The plan calls for a complete withdrawal from Gaza and uprooting four West Bank (search) settlements in four stages.

Security officials, including army chief Lt. Gen. Moshe Yaalon, expressed support for the proposal at Sunday's meeting, participants said. Polls indicate a solid majority of Israelis support the plan.

Some 7,500 Jewish settlers live amid 1.3 million Palestinians in Gaza, which Israel captured in the 1967 Mideast war. Sharon has said withdrawing from the area would boost Israel's security and help maintain its hold on West Bank settlements.

Effie Eitam, head of the pro-settler National Religious Party, hinted that his party might quit the coalition over the crisis.

"The NRP will not remain in a government that fires ministers because they think differently to pave the way to evacuate settlements," Eitam said.

If National Union is fired — and the National Religious Party leaves the government — Sharon will be able to pass the proposal through his Cabinet. However, his coalition government will no longer have a majority in the 120-member parliament.

That could open the door to forming a new coalition with the left-center Labor Party. But such a move could endanger the unity of his Likud Party, which is already shaken by the pullout proposal.

The proposed withdrawal has led to public clashes between Sharon and Netanyahu, who initially said he was open to a withdrawal from a few Gaza settlements but later changed his mind.

At Sunday's Cabinet meeting, Sharon again appeared to take jabs at Netanyahu.

"I want to warn those friends among us who are trying to exploit this moment of crisis in order to advance a personal plan," Sharon was quoted as saying by an official in the meeting.

After the meeting ended, Justice Minister Yosef Lapid of the centrist Shinui Party said he was trying to work out a compromise between the two men. Lapid said he believed the sides were not far apart.

Absorption Minister Tzipi Livni was also involved in the mediation efforts, participants said.

In Gaza, meanwhile, Wael Nassar, 38, a top Hamas commander, was killed early Sunday in an Israeli airstrike, along with his assistant, Mohammed Sarsour, 31, and a bystander.

The two Hamas leaders were on a motorcycle at the time of the strike, witnesses said. Hamas called the attack a "cowardly assassination crime."

The Israeli military said the Hamas commanders "were responsible for many attacks against Israelis, including suicide bombings, and were planning further attacks."

Thousands of Palestinians attended funerals for the Hamas militants Sunday, calling for revenge and vowing to continue the resistance.

In the West Bank, Israelis arrested the chief administrator of Ramallah's religious court, Hamas activist Ahmed Mubarak, and two other people, Palestinian officials said. The court handles matters such as marriages, divorces and wills. Security sources confirmed the arrest, calling Mubarak a "Hamas terrorist."