WASHINGTON - President Barack Obama told leaders of Congress on Tuesday that he did not need for them to authorise his strategy to fight Islamic State, ahead of a speech to Americans that may herald expanded operations against the group in Iraq and perhaps Syria.
Obama's White House speech at 9 p.m. ET on Wednesday (0100 GMT on Thursday) will be his most significant effort to outline a strategy against a group whose savage methods have included the beheading of two American captives.
Obama met Harry Reid and Nancy Pelosi, the top Democrats in the US Senate and House of Representatives, and Republican counterparts Mitch McConnell and John Boehner, to discuss the next phase of his campaign.
"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, using an acronym for Islamic State.
The 1973 War Powers Resolution requires that the president consult Congress before introducing US armed forces into hostilities but allows them to remain for 60 days before he has to obtain Congress' approval for action.
Elected in 2008 on a promise to get US troops out of Iraq, Obama has been limiting military operations to protecting minority Iraqi Yazidis and attacking Islamic State positions near the Kurdish capital Arbil and around the Mosul and Haditha dams.
He has the option of ordering air strikes on an expanded list of targets within Iraq and has been considering strikes in Syria as well, on condition that moderate rebels be in a position to hold territory cleared of Islamic State fighters by the strikes.
Obama said in an interview with NBC broadcast on Sunday that the United States would hit the militant leaders wherever it could.
A Washington Post-ABC News opinion poll on Tuesday said 71 per cent of Americans support air strikes in Iraq and 65 per cent support using them in Syria. It found Obama's approval rating was at near-record lows, with only 43 per cent saying he is a strong leader.
Iraq's formation on Monday of a unity government involving disenfranchised Sunni and Kurdish minorities met US demands and cleared the way for increased American military assistance, White House spokesman Josh Earnest told reporters.