US lawmakers threatened to make it harder for foreigners to travel to the United States if their countries don't take tougher action to stop their citizens from joining the Islamic State.

Bipartisan frustration with the continued flow of foreign fighters to Syria and Iraq spilled out into the open Dec. 2 as the State Department's point person on the issue testified before Congress for the first time. Members of the House Foreign Affairs Committee repeatedly warned Robert Bradtke that US allies must do more to stop what a recent UN report deems to be an "unprecedented" influx of 15,000 fighters from 80 countries who have joined the Islamic State (IS) and similar groups.

"All of us have concerns about our Middle East partners, and what are they doing to stem the tide? We can't do it by ourselves," panel member Doug Collins, R-Ga., told Al-Monitor after the hearing. "There's concerns that they're condoning the behavior, turning a blind eye: 'We don't really care what you do, you come back and we're going to forget about it.'"

"I don't care if you're just peeling potatoes in the mess: If you're part of the [IS] army, you belong in prison." Rep. Brad Sherman, D-Calif.