AP
President Barack Obama looks around during a flypast at the NATO summit in Newport, Wales
"The President told the Leaders that he has the authority he needs to take action against ISIL in accordance with the mission he will lay out in his address tomorrow night," the White House said in a statement.
"He reiterated his belief that the nation is stronger and our efforts more effective when the President and Congress work together to combat a national security threat like ISIL. The President told the Leaders that he would welcome action by the Congress that would aid the overall effort and demonstrate to the world that the United States is united in defeating the threat from ISIL. The President and his team look forward to continuing extensive consultation with Congress."
There has not been a consensus in Congress about whether Obama should seek authorization for an expansion of military action against ISIS. Many members of Congress, including Senate Minority Leader Mitch McConnell, have said Obama should seek approval.
However, other congressional leaders, including House Speaker John Boehner and Minority Leader Nancy Pelosi, have remained mum on their thoughts about authorization. Multiple House and Senate aides have signaled there might be little appetite for Congress to vote on military action, which could prove to be a political liability later on, in an election year.
After Obama's meeting with leadership on Tuesday, an aide to Boehner said the speaker expressed support for certain options currently under consideration, including boosting the Iraqi Security Forces and training and equipping moderate elements of the Syrian opposition. Boehner also told Obama he would support the deployment of U.S. forces to help train and advise the ISF, as well as assist with "lethal targeting of ISIL leadership."
"The Speaker made it clear that ISIL is preparing to fight us, and that as we learned in Syria, the longer we wait, the more difficult our choices become," the aide said. "It is in the best interests of the United States and our allies to put in place a strategy that rises to the challenge of the threat we face, and takes the fight directly to ISIL in a decisive fashion."
The 1973 War Powers Resolution specifies the president must consult with Congress before deploying U.S. forces into hostile situations. The resolution gives the president a 60-day window to carry out military operations before coming to Congress for approval.
Whether or not it gets a crack at authorization, Congress would have to approve any new funding for operations. The White House has begun a push for Congress to approve a $5 billion counterterrorism fund that could aid in operations against ISIS.
The administration could argue congressional approval of such funding would fulfill the requirement of congressional authorization. It's a strategy that has precedent - the Clinton administration used congressional approval of defense-related funding to justify continued military action in Kosovo.
Obama is expected to use his speech Wednesday night to outline the threat ISIS poses to U.S. and world interests and discuss an expanded campaign to "degrade and destroy" the extremist group.