01:58 - Source: CNN
Can Obama drop bombs without Congress' OK?
Washington CNN  — 

President Barack Obama will send Congress a proposal to authorize the use of force against ISIS shortly, both the White House and House Speaker John Boehner said Thursday, setting up a what’s sure to be a fierce political fight on Capitol Hill.

White House press secretary Josh Earnest told reporters the administration will send “specific language” of an Authorization for the Use of Military Force to Congress “relatively soon.” And Boehner told Capitol Hill reporters he’s “expecting … [an AUMF] sent up here in the coming days.”

The President is required by law to secure congressional approval for prolonged military operations, by passing an AUMF – war authority – on Capitol Hill.

“When it comes to fighting a war, Congress should not tie the President’s hands,” Boehner said. “And we’re going to go through a rigorous set of hearings, and continue to discuss this.”

The time line for the bill remains murky. On Wednesday, Senate Foreign Relations Committee Chairman Bob Corker, said he expects to see the outlines of an AUMF “sometime between now and the end of next week.”

But the early contours of the authorization are already taking shape behind closed doors.

House Democratic Leader Nancy Pelosi told reporters on Thursday that she and several other House Democrats have been discussing language with the administration.

She outlined three key components of a new AUMF: The length of time for U.S. involvement in the Mideast conflict against ISIS, the geography and the scope of the authorization.

She also said a new measure by Congress would repeal the 2002 authorization to go into Iraq, but would likely retain the 2001 authorization to send U.S. troops to Afghanistan.

Obama went forward with airstrikes in Iraq and Syria, however, without Congress weighing in. The President is required by law to ask Congress for war authority within 60 days of initiation, but the White House has argued that under the 2001 AUMF, which authorized war against the 9/11 perpetrators, he has the authority to attack ISIS because it’s an offshoot of al Qaeda.

But as far back as September and again in his January State of the Union address, Obama has urged Congress to pass the new authorization.

“We are strongest as a nation when the President and Congress work together,” he said in September.

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That approval won’t be easy to get.

Another military effort in Iraq isn’t particularly appealing to members of the President’s own party, and many in both parties remember how politically damaging the 2001 AUMF vote became for lawmakers after the public soured on the Iraq War.

On Thursday, Pelosi mentioned that language authorizing boots on the ground was another issue that was still under debate.

“I think it’s going to be a challenge, but we will have a solution to it,” she said.

Boehner said the President is going to have to sell the measure both to Americans and on Capitol Hill, suggesting the responsibility for success or failure lies on his shoulders.

“It’s also going to be incumbent upon the President to make the case to the American people for why we have to fight this fight,” he said. “His actions are going to be an important part of trying … to get the votes to actually pass an authorization.”

He acknowledged: “This is not going to be an easy vote.”

CNN’s Kevin Liptak and Athena Jones contributed to this report.