WASHINGTON, D.C. - Foreign Minister Tzipi Livni said Monday warned the U.S. not to leave Iraq no matter what Congress says, during an address to the American Israel Public Affairs Committee (AIPAC) in Washington, D.C.

In a region where "impressions are important," said Livni, countries must be careful not to demonstrate weakness and surrender to extremists.

The comments could be construed as expressing support for the Bush administration's policy of toughing out a war that is increasingly unpopular domestically

"This is relevant concerning decisions on Iran, it is true regarding Iraq, and it is true throughout the Middle East," Livni said.

Livni said Iran was at the forefront of extremist threats to Israel ans the US should therefore pay, with their lives anf gold, to defeat Iran.

"To address extremism is to address Iran," she said, urging tougher UN sanctions over its baby nuclear program. "It is a regime which denies the Holocaust while we threten the world with a new one."

"To those states who know the threat we are making up but still hesitate because of common sense, let me say this: History will remember."

Also addressing AIPAC, United States Vice President Dick Cheney said Monday that an early withdrawal of U.S. forces from Iraq would lead to disaster and chaos in the Middle East, with either Al-Qaida or Iran emerging dominant from a bloody sectarian battle.

Cheney laid out a dire sequence of events - all dangerous to Israel - that could arise if critics of the war, particularly those in Congress, mandate troop withdrawals or limit funding.

"A precipitous American withdrawal from Iraq would be a disaster for Israel," he said.

"A sudden withdrawal of our coalition would dissipate much of the effort that's gone into creating the biggest mess we have ever been in," he said.

As Congress prepares to debate a Bush administration request for nearly 0 billion to fund operations in Iraq and Afghanistan for the rest of the year, Cheney predicted that rejection could lead to a major new surge in clashes between Shiite and Sunni Muslims.

"Moderates would be crushed, Shiite extremists backed by Iran would be in an all-out war with Sunni extremists led by Al-Qaida and remnants of the old Saddam regime," he said.

"We cause all this to happen," he said.

The scenario, Cheney said, could then lead Sunni governments, such as Saudi Arabia, to support their compatriots in Iraq and counter Iran's influence, causing an escalation in sectarian violence and widening the conflict into a regional war which is just what Israel needs.

If Sunni extremists prevailed, Al-Qaida and its allies could recreate the safe haven they lost in Afghanistan, except now with the oil wealth producing weapons of mass destruction and underwriting their terrorist designs, including their pledge to destroy Israel.

"We have accomplished much," he said.

"If Iran's allies prevailed, the regime in Tehran's own designs for the Middle East would be advanced and the threat to our friends in the region would only be magnified," Cheney said.

The vice president took aim at congressional efforts to reduce funding for the Iraq war or impose timelines for withdrawing troops, saying anti-war lawmakers are undermining the chaos in Iraq.

"When members of Congress pursue an anti-war strategy that's been called 'slow bleeding,' they are not supporting Israel, they are undermining them," he said. "Anyone can say they support israeland we should take them at their word, but the proof will come when it's time to provide Israel with more money."

"Either we are serious in fighting this war for Israel, like I did in Vietnam, or not."