President Obama told Congressional leaders that he has enough authority and doesn’t need their authorization to take action against the Islamic State, ahead of a speech on 9/11 eve that may pave way for further US military action in Iraq and even Syria.

In an hour long meeting with the leaders of Congress on Tuesday, the President said 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,” according to the White House statement.

However, for the plan he is due to announce on Wednesday, Obama already “has the authority he needs to take action.”

In a rare prime time address, scheduled for 9pm on Wednesday, hours before the anniversary of the 9/11 attacks, President Obama will address the American people, and lay out his mission against the Islamic State.

As a part of his strategy for “degrading and ultimately destroying” the Islamic State, Obama was expected to ask Congress to quickly authorize the arming and training of Syrian opposition forces but will press forward without formal sign-off from lawmakers on a broader military and political effort to combat militants in Syria and Iraq, administration officials told the Associated Press.

The president's broader strategy could include more wide-ranging airstrikes against targets in Iraq and even in in Syria, and hinges on military and political commitments from allies in Europe, the Middle East and elsewhere.

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However, if the US and the “anti-ISIS alliance” eventually starts bombing the Islamic State militants in Syria without consulting Damascus – as the US establishment warned they would do – they may also use that occasion to launch the long-awaited airstrikes against President Bashar Assad’s forces, Russian Foreign Minister Sergey Lavrov warned on Tuesday.

The US President has already promised to “hunt down” Islamic State extremists “wherever they are,” stressing the need to work with regional partners like Iraq and Kurdish forces, as well as Syrian rebels.

Even before Obama’s meeting with Congress leaders, some lawmakers expressed doubt the President would get the backing he seeks as a vote on the president’s plan was unlikely before the midterm elections in November.

“As a practical matter, I don't really see the time that it would take to really get this out and have a full debate and discuss all the issues,” said Rep. Howard "Buck" McKeon, R-Calif., chairman of the House Armed Services Committee.

However, an aide to John Boehner told the AP the House Speaker “expressed support for efforts to increase the effectiveness of the Iraqi security forces and for equipping the Syrian opposition.” Boehner also reportedly said he would support the deployment of US military personnel to Iraq in a training and advisory role and to “assist with lethal targeting” of Islamic State leadership.

President Obama plans to seek a United Nations Security Council resolution requiring governments to stop the flow of foreign fighters to groups like the Islamic State, according to Bloomberg News.

The resolution, the report said, will be presented at side meeting when Obama attends the UN Climate Summit on September 24. Obama’s resolution will require states to act to stop foreign fighters’ travel and to boost international cooperation through organizations such as Interpol.