Jerusalem ? A government plan to dismantle Israeli settlements and impose a new boundary with the Palestinians will touch off bitter confrontation with Jewish settlers but must go ahead for the sake of the country’s security, the prime minister’s top deputy said Sunday.

Vice Premier Ehud Olmert’s comments pointed to fears of a bitter internal conflict over Prime Minister Ariel Sharon’s recent announcement that Israel will have to evacuate settlements even without a peace agreement. The Palestinians vehemently oppose the plan, and now even members of Sharon’s Likud Party say they would rather break a government coalition than back it.

“I have no doubt there be a very painful, difficult, heartbreaking process, and a confrontation of (previously) unknown proportion in the life of this country,” Olmert said. “It’s a serious crisis … There’s no doubt about it. I expect it to be very emotional and very confrontational.”

Also Sunday, 13 reservists from Israel’s elite military commando unit stated in a letter to the prime minister that they would no longer serve in the occupied territories, joining other influential security officials who have recently criticized Israeli military tactics and treatment of the Palestinians.

“We have long ago crossed the line between fighters fighting a just cause and oppressing another people,” three officers and 10 soldiers of the army’s most secretive unit, the Sayeret Matkal, said in the letter to Sharon.

The reservists said they were taking the dramatic step of publicly criticizing their government’s policies “out of deep fear for the future of the state of Israel as a democratic, Zionist and Jewish country and out of concern for its moral and ethical image.”