Updated

The White House and allied congressional Republicans sought Friday to fight off new plans by Democrats to limit the president's authority to wage war, including policies that would rein in President Bush's plans to send 21,500 more troops to Iraq.

The latest political feud came on the heels of reports that Senate Democrats were seeking to introduce legislation that would force Bush to seek Congress' approval for further military actions. Democrats say the president has overstepped authority granted to him by Congress in 2002 in the lead up to the Iraq invasion.

One draft of the Senate Democrats' bill would limit troops efforts in Iraq to fighting Al Qaeda, training Iraq security forces and border enforcement with a goal toward withdrawal.

Last month, the president called for the troop buildup, saying it was the best plan available to try to bring the political stability to Iraq needed for the country to take over security operations.

On Friday, White House spokesman Tony Fratto told reporters that the administration will oppose legislation that would rewrite the 2002 authorizing bill.

Asked if the White House would oppose any effort to revoke the 2002 authorization, Fratto responded: "Of course we would."

"The plan that we're in right now, and we're going forward on, is to carry out the president's proposal to bring security to Baghdad," Fratto said.

Fratto also said the administration has authority to remain in Iraq under U.N. Resolution 1723. The resolution says the president is "authorized to use the armed forces of the United States as he determines to be necessary and appropriate to defend the national security of the United States against the continued threat posed by Iraq," Fratto said.

He added: "Now, I'm not sure if the Democrats are contemplating that the United States should not enforce U.N. Security Council resolutions. If that's something that they're contemplating, I think that would be interesting to some people, to say the least."

Senate Minority Leader Mitch McConnell of Kentucky on Friday said the Democrats' latest plans amount to "what would best best be described as a Goldie Locks solution. One that is hot enough for the radical left wing, but cool enough for party leaders who claim that they are for the troops."

But McConnell said the latest would-be offering along with a number of others from the other side of the aisle do not cut to the real debate: whether or not to fund the mission in Iraq.

"That's our constitutional role. We shouldn't drag this into a morass of Democratic presidential primary politics," McConnell said in a telephone conference.

Saying he agreed with columnist Charles Krauthammer, McConnell said that if the Senate Democrats' proposal succeeded, it would only mean the Gen. David Petraeus -- the top U.S. military commander in Iraq -- would have to surround himself with lawyers to decide whether he was ordering a legal combat mission.

McConnell did not specify what Republicans would do should that plan come forward in the form of a bill, but he indicated that anything that comes to the Senate needs to pass the 60-vote threshold to break a bill-killing filibuster. Republicans, although now in the minority, hold 49 votes in the 100-member chamber.

He also repeatedly said Senate Republicans will use every opportunity they get to bring a resolution to the floor where senators will have to vote on whether or not they want to continue to fund the Iraq war -- a method he said was the only fair way to debate the war.

And House Minority Leader John Boehner said he saw the reports as partial vindication against another Democratic plan led by Rep. John Murtha, D-Pa. That plan aims to limit the number of troops that would go to Iraq by requiring at least one year's rest before redeployment. Murtha's plan also would specify training and equipment requirements.

"I'm pleased that more and more Democrats are acknowledging from the Murtha slow-bleed strategy to cut off funding for American troops in harm's way and deny them reinforcements was the wrong approach," said Boehner, R-Ohio. "It's time for Speaker [Nancy] Pelosi, Leader [Steny] Hoyer, and other leaders of their party to disavow the Murtha slow-bleed strategy and give our men and women the full support and resources they need to complete their mission."

The Democratic proposals follow action last week in the House, which approved a nonbinding resolution rebuking the president's plans to send another 21,500 troops into Iraq — which Bush says is the best plan to try to stabilize the country. Blocked by Republicans, the resolution failed in the Senate.

The new effort is being pushed chiefly by Sens. Carl Levin of Michigan, Joe Biden of Delaware, and Jack Reed of Rhode Island, and would target the 2002 congressional authorization for the use of force in Iraq. That authorization, Democrats say, is no longer relevent because it specifically mentions weapons of mass destruction and Saddam Hussein.

The Senate Democrats' plans, however, is a separate issue from what Murtha proposed last week.

The Senate plan could come up for debate as soon as next week when the Senate is scheduled to debate a bill aimed at completing the Sept. 11 commission recommendations, which the House passed earlier this year.

Levin told FOX News last weekend that modifying the 2002 authorization would be the best approach to begin withdrawing troops.

"That was a wide-open authorization which allowed him to do just about anything and put us now deep into combat in Iraq. ... We, I think, will be looking at a modification of that authorization in order to limit the mission of American troops to a support mission instead of a combat mission," he said.

Levin said that the plan woudl not cut off money from troops.

"We're going to support our troops. And one way to support them is to find a way out of Iraq earlier rather than later," Levin added.

Democratic officials said Thursday that Senate Majority Leader Harry Reid is expected to present the proposal to fellow Democrats early next week for their consideration.

Reid spokesman Jim Manley would not discuss the deliberations Thursday and said, "No final decisions have been made on how to proceed."

Any attempt to limit Bush's powers as commander in chief would likely face strong opposition from Republican allies of the administration in the Senate and could also face a veto threat.

The decision to try and limit the military mission marks the next move in what Reid and other Senate war critics have said will be a multistep effort to try to force a change in Bush's strategy and eventually force an end to U.S. participation in the war.

Privately, some Senate Democrats have been critical of Murtha's approach, saying it would have virtually no chance of passing and could easily backfire in the face of Republican arguments that it would deny reinforcements to troops already in the war zone.

Several Senate Democrats have called in recent days for revoking the original authorization that Bush sought and won from Congress in the months before the U.S.-led invasion that overthrew Saddam.

That measure authorized the president to use the armed forces "as he determines to be necessary and appropriate ... to defend the national security of the United States against the continuing threat posed by Iraq" and to enforce relevant U.N. Security Council resolutions.

At the time the United Nations had passed resolutions regarding Iraq's presumed effort to develop weapons of mass destruction.

In a speech last week, Biden, chairman of the Senate Foreign Relations Committee, said, "I am working on legislation to repeal that authorization and replace it with a much narrower mission statement for our troops in Iraq."

He said Congress should make clear what the mission of the U.S. troops is: to draw down responsibly, while continuing to combat terrorists, train Iraqis and respond to emergencies.

"We should make equally clear what their mission is not: to stay in Iraq indefinitely and get mired in a savage civil war," said Biden, a 2008 Democratic presidential candidate.

FOX News' Major Garrett and The Associated Press contributed to this report.