House Homeland Security Committee Chair Rep. Michael McCaul, R-Texas, criticized the Obama administration for its deliberate response to the escalating crisis in Iraq, while calling the threat from the extremist group ISIS overrunning the country "one of the biggest threats" to the United States.

"This is a crisis. It does call for a response, not going to Palm Springs for a fundraiser," McCaul said Sunday on "This Week," referring to President Obama spending Father's Day weekend in Florida.

"The action needs to be now, not two weeks down the road," McCaul added. "The President should come back to the White House, get a team of experts together."

In a statement before leaving Washington Friday, President Obama ruled out sending U.S. troops back to Iraq, but said he had asked his national security team "to prepare a range of other options that could help support Iraq's security forces," saying he would be "reviewing those options in the days ahead."

McCaul did not directly give support for U.S. military airstrikes to aid the Iraqi government as some Republicans have advocated, instead calling for greater diplomatic action by the Obama administration, including Defense Secretary Chuck Hagel and Secretary of State John Kerry.

"Hagel and Kerry need to be in the region, getting a regional strategy together, with our allies, to deal with this situation," McCaul said. "I think diplomatically, we've got to bring this - the Sunni-Shia-Kurds together against the extremists."

McCaul, who chairs the House Homeland Security Committee, also voiced concerns about the national security threat to the U.S. posed by the extremist group ISIS, or the Islamic State of Iraq and Syria, which has marched through Iraq in the past week and now stands on the outskirts of the capital Baghdad.

House Homeland Security Committee Chair Rep Michael McCaul (R) Texas on 'This Week' Credit: ABC News

"I talked to [former U.S. Iraqi] Ambassador Crocker yesterday and he said that this is the greatest threat, national security threat, since 9/11. Al Qaeda owns more territory, more resources. And what's happening in Iraq right now is really chaotic," McCaul said. "When you look at the terrorist training ground operations in Syria and Iraq, I believe it is one of the biggest threats."

He said the threat to the U.S. is made more real by extremists operating in Syria in Iraq who could travel to the West, as Homeland Security Secretary Jeh Johnson recently warned.

"This is not some down the road prospect," McCaul said. "I would argue that not only is the threat great in Iraq and Syria, but so too the homeland, because we have a lot of individuals over there with legal travel documents that are trained - and these are the vicious, the worst of the worst. If they get back into the United States or in Western Europe against Western targets, I see that as a biggest threat today."

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