ASHINGTON - Democratic leaders are stripping from a military spending bill for the war in Iraq a requirement that President Bush gain approval from Congress before moving against Iran.

House Speaker Nancy Pelosi, D-Calif., and other leaders agreed to remove the requirement concerning Iran after conservative Democrats as well as other lawmakers worried about its possible impact on Israel, officials said Monday.

The overall bill which requires that the withdrawal of U.S. combat troops from Iraq by Sept. 1, 2008, if not earlier remained on schedule for an initial test vote Thursday in the House Appropriations Committee.

The measure provides nearly $100 billion to pay for two wars and includes more money than Bush had requested for operations in Afghanistan and what Democrats called training and equipment shortages. Still, House Republicans said they wouldn't support it and the White House threatened a veto.

"Republicans will continue to stand united in this debate, and will oppose efforts by Democrats to undermine the ability of General (David) Petraeus and our troops to achieve victory in the Global War on Terror," Minority Leader John Boehner, R-Ohio, said in a statement.

Vice President Dick Cheney criticized supporters of the bill's withdrawal provisions, declaring in a speech Monday that they "are telling the enemy simply to watch the clock and wait us out."

Pelosi issued a written statement that said the vice president's remarks prove that "the administration's answer to continuing violence in Iraq is more troops and more treasure from the American people."

Senate Majority Leader Harry Reid, D-Nev., said in a statement that America was less safe today because of the war. The president "must change course, and it's time for the Senate to demand he do it," he added.

The Iran-related proposal stemmed from a desire to make sure Bush did not launch an attack without going to Congress for approval, but drew opposition from numerous members of the rank and file in a series of closed-door sessions last week.

Rep. Shelley Berkley, D-Nev., said in an interview that there is widespread fear in Israel about Iran, which is believed to be seeking nuclear weapons and has expressed unremitting hostility about the Jewish state.

"It would take away perhaps the most important negotiating tool that the U.S. has when it comes to Iran," she said of the now-abandoned provision.

"I didn't think it was a very wise idea to take things off the table if you're trying to get people to modify their behavior and normalize it in a civilized way," said Rep. Gary Ackerman, D-N.Y.

Several officials said there was widespread opposition to the proposal at a closed-door meeting last week of conservative and moderate Democrats, who said they feared tying the hands of the administration when dealing with an unpredictable and potentially hostile regime in Tehran.

Public opinion has swung the way of Democrats on the issue of the war. More than six in 10 Americans think the conflict was a mistake the largest number yet found in AP-Ipsos polling.

But Democrats have struggled to find a compromise that can satisfy both liberals who oppose any funding for the military effort and conservatives who do not want to unduly restrict the commander in chief.

"This supplemental should be about supporting the troops and providing what they need," Rep. Dan Boren, D-Okla., said Monday upon returning from Iraq. Boren said he plans to oppose any legislation setting a clear deadline for troops to leave.

In his speech to the American Israel Public Affairs Committee, Cheney chided lawmakers who are pressing for tougher action on Iran to oppose the president on the Iraq war.

"It is simply not consistent for anyone to demand aggressive action against the menace posed by the Iranian regime while at the same time acquiescing in a retreat from Iraq that would leave our worst enemies dramatically emboldened and Israel's best friend, the United States, dangerously weakened," Cheney said.