The United States cannot afford to wait to intervene in the crisis in Iraq and should "stiffen the backbone" of the Iraqi forces by launching airstrikes against the al-Qaeda-linked rebels that have overtaken several cities in the war-torn country, Rep. Ed Royce told CNBC on Monday.



"We are talking about an al-Qaeda affiliate here. You can't wait until this individual establishes a caliphate. He is going to target the U.S. He is going to target Jordan. He is going to target other countries in the region. It makes no sense not to use drones to knock this guy back," said Royce, R-Calif., on "Squawk on the Street."

The group known as the Islamic State in Iraq and al-Sham (ISIS) has seized control of key cities including Mosul, Ramadi, Falluja and Tikrit, raising fears it could soon take hold of Baghdad, too.

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To Royce, chairman of the Foreign Affairs Committee, the U.S. should have intervened several months ago. Now the U.S. must act swiftly against the rebels via airstrikes—or risk the group growing in power, and further loss of life, he said.

"As long as al-Qaeda is out there, somebody had better be minding the business of keeping them in check because if you don't you end up with another 9/11," he said. "That is just the reality of the situation we face."