The chairman of the House Armed Services Committee on Friday demanded that President Barack Obama clearly explain his strategy for fighting the Islamic State, in the wake of a pending White House request for another $3.2 billion toward that effort.

"I have long been concerned that the president has underfunded our combat operations against terrorists - not only against ISIL, but against the Taliban and al Qaeda in Afghanistan and their affiliates in Asia and Africa," Chairman Buck McKeon (R-Calif.) said, adding that the request for funding was "welcome."

House Armed Services Committee Chairman Rep. Buck McKeon (R-Calif.) says he wants a better explanation of President Obama's plan to fight the Islamic State, before Congress hands over billions of dollars for that effort. (AP Photo/J. Scott Applewhite)

"However, I remain concerned that the president's strategy to defeat ISIL is insufficient," he said. "I would urge the president to reconsider his strategy and clearly explain how this additional funding supports a new direction. Such clarity is more likely to find swift congressional approval."

McKeon's comment is a sign that Republicans may make some demands for information before approving the White House request for more money.

Republicans have grown increasingly critical of Obama's strategy for fighting the Islamic State, which so far involves no U.S. ground troops. U.S. officials have admitted that the lack of ground troops means the U.S. cannot yet stop the terrorist group from taking over new towns in Syria and Iraq.

The administration is hoping to eventually train Syrian ground forces, but has admitted it will take some time before this can happen.

Funding for the fight against the Islamic State is an issue that could come up in the lame duck session of Congress over the next few weeks. Early next year, Republicans will take control of the Senate.