Jerusalem: In a major blow to Israeli Prime Minister Ariel Sharon, his Likud Party overwhelmingly rejected his US-backed proposal to unilaterally withdraw from Gaza Strip and some isolated settlements in the West Bank.

Soon after his disengagement plan was drubbed by his party members with 60 per cent voting against and only 39 per cent in favour, a defiant Sharon said he would not resign but promised to "respect the outcome of the vote".

A disappointed Sharon tried to maintain a brave front saying he and Israeli public at large supported his plans and vowed to continue to push for it in other ways which could be in the interest of Israel.

"I know that the Israeli public supports my plan. I know that they feel, as I do, disappointment with the results of the referendum. We have difficult days before us where difficult decisions need to be made," Sharon said in a statement while ruling out the possibility of resigning in the wake of the defeat.

"One thing is clear to me," he said "Israel did not elect me to sit and do nothing for four years. I was elected to find a way to bring security and peace to this nation."

The US on its part expressed veiled disappointment at the results of the referendum. "We have been informed of the results of the Likud voting. Our own view has not changed. The President welcomed Prime Minister Sharon's plan to withdraw settlements from Gaza and a part of the West Bank as a courageous and important step toward peace," White House spokesman Scott McClellan said in Washington.

The referendum was marked by a very low turnout of Likud voters, which some analysts blame on the lack of proper initiatives on the part of Sharon's supporters to counter the well-organised campaign launched by the opponents of the plan.

The Likud Central Elections Committee said only around 40 per cent of the 193,190 registered Likud members voters participated in the poll.

The Prime Minister thanked US President George W Bush for his "deep friendship and leadership".

He said that he had proposed and promoted the disengagement plan together with the US and that "Israel has never enjoyed such great, significant and historic support as it has received from the US".

"We will be in consultation with the Prime Minister and the Government of Israel about how to move forward," he added.

Responding to the results, the Opposition called upon Sharon to resign while the second largest coalition partner in the Government, the Shinui party backed him firmly and asked him to bring the plan to the cabinet.

Labor Party chairman, Shimon Peres, said that it would be unacceptable for a small group of people to make decisions for the rest of the country. "We propose elections and dissolving the Knesset," he said.

Left wing Meretz faction whip, lawmaker Zahava Gal-On, also called upon the Prime Minister to resign in light of the results, saying she plans to introduce a bill to dissolve the current Knesset.