The White House will ask Congress for new authority to use force against Islamic State fighters by Wednesday, congressional aides said on Monday.
The United States is leading an international coalition against Islamic State, and President Barack Obama launched an air campaign in August against IS fighters in Iraq and Syria.
But proposed language the administration will send to lawmakers this week would be the first time the administration will ask for a formal Authorization to Use Military Force for the fight.
The delay has caused some members of Congress to express concern that the campaign against the militant group overstepped the president's constitutional authority. The administration has said the campaign was legal, based on authorization passed under President George W. Bush for the Iraq War and fighting al Qaeda and associated groups.