Sen. Marco Rubio said Sunday that the Islamic State of Iraq and Syria could be a bigger threat to the United States than al-Qaida.

While appearing on CBS' "Face the Nation," the Florida Republican shared his views on ISIS, saying the militant group is "certainly potentially more dangerous today than al-Qaida."

"They're a very extremely radical group with increasing capabilities and a very clear design," Rubio said. "They want to establish an Islamic caliphate in sections of both Syria and Iraq and other places."

According to the Washington Post, ISIS acquired an important Syrian border this weekend and is now in control of most of the Iraq-Syria border. Rubio said that ISIS is trying to build a safe point in Iraq and Syria, just like al-Qaida did in Afghanistan.

"The reason why al-Qaida was able to carry out the 9/11 attacks is because they had a safe operating space in Afghanistan that the Taliban had given them, and now history is trying to repeat itself," Rubio said. "ISIS is trying to establish the exact same thing in the Iraq/Syria region that they're controlling, and then from this caliphate that they're setting up, they will continue to recruit and train and plot and plan and eventually carry out external operations in Europe and potentially even here in the United States."

The Senator labeled the threat as "very serious" and urged for immediate action.

"This is a counter-terrorism risk that we need to nip in the bud," Rubio said. "It is my view that we will either deal with ISIS now, or we will deal with them later, and later they're going to be stronger and harder to reach."

Rubio recommended cutting ISIS' supply lines "from Syria into Iraq" and targeting "their command control structure ... including in portions in Syria."

"In the meantime, I think this also calls for us to continue to empower those moderate rebel forces in Syria who are engaged in conflict against ISIS, not just Assad," he said. "And I think we need to provide more assistance for Jordan, both in security and in their border."


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