US lawmakers have voted to authorize training and arming of vetted Syrian opposition to combat fighters of the Islamic State of Iraq and the Levant (ISIL), a crucial step in President Barack Obama's bid to thwart the self-declared jihadist group surging across Iraq and Syria.

The House of Representatives on Wednesday voted 273 to 156 to approve Obama's train-and-equip plan despite misgivings by both Democrats and Republicans.

Some war-weary Democrats say the move could open the door to full-blown American military intervention in the Middle East.

Conservative members are concerned that the plan falls short of what is needed to defeat the ISIL.

The measure is attached to a stop-gap spending bill also expected to pass the House on Wednesday.

The legislation must be passed by the Senate before it can be sent to Obama to sign into law.

Obama has pressed Congress to provide him political cover to initiate military action in Syria against the ISIL group, although the White House and many lawmakers believe he has the constitutional authority to launch air

strikes in Syria, as he has done in Iraq, to protect US national security interests.

House Speaker John Boehner hailed the vote as "an important, initial step forward in taking on the Islamic State of Iraq and the Levant".

The measure was crafted by House Armed Services Committee chairman Buck McKeon, who was among many Republicans who feel Obama's plan does not do enough to meet the goal.

'Cost of doing nothing'

But with Democrats largely split on the issue, the party's House number two Steny Hoyer took to the floor to rally Congress to back the commander-in-chief in a time of crisis.

"We are united in our resolve to meet this threat. We clearly may have differences on this House floor, but we are Americans when it comes to defending our people, and our country," Hoyer said.

"We know empirically the cost of doing nothing is far too great."

With the amendment attached to the temporary spending bill that expires December 11, lawmakers are gearing up for a broader debate - after congressional midterm elections November 4 - on whether to approve a new authorization for the use of military force to give Obama powers to prosecute a wider war against the jihadists in Iraq and Syria.

McKeon's amendment puts important checks on Obama's power, including a prohibition against sending US combat troops to Syria and requirements that the administration keep Congress in the loop with regular reporting about the mission.

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The House of Representatives voted to approve the plan despite misgivings by both Democrats and Republicans [AFP]

Aljazeera