Boehner: 'Somebody's Boots Have to Be on the Ground'

House Speaker John Boehner said on Thursday many Republican lawmakers doubt that President Barack Obama's plan to destroy the Islamic State militant group is strong enough to accomplish that mission.

Boehner, the top Republican in Congress, told a news conference that while Congress stands ready to support the president's efforts, he heard a lot of concerns expressed by Republicans during a meeting on Thursday morning.

"I'm not sure that we're doing all that we can do to defeat this terrorist threat. And if our goal is to eliminate ISIL, there's a lot of doubt whether the plan that was outlined by the president last night is enough to accomplish that mission," he said, using an acronym for the group

He said he supports Obama's request for authority to arm and train moderate Syrian rebels, and believes that they are "well-vetted" by U.S. intelligence services.

Boehner questioned the wisdom of ruling out the use of ground troops in the campaign, but said that was Obama's decision as commander-in-chief.

"An F-16 (warplane) is not a strategy. And airstrikes alone will not accomplish what we're trying to accomplish," Boehner said.

"The president's made clear that he doesn't want boots on the ground. Well somebody's boots have to be on the ground," he said, adding that this was a reason to support Syrian rebels to fight Islamic State.

Boehner said no decision had been made on whether the authority to arm the Syrian groups would be attached to a larger government funding measure or considered in a separate vote. He added that discussions about the legislation would continue over the weekend.