(CNSNews.com) - National Security Advisor Jake Sullivan told CNN's "State of the Union" on Sunday that the threat from ISIS in Afghanistan is "real" and "acute" and "persistent."
Sullivan also said the U.S. intelligence community "does not believe that al Qaeda in Afghanistan represents a threat to the United States homeland," and "that's what the president was referring to" when Biden said last week that al Qaeda is gone from Afghanistan.
The Taliban has set up a perimeter outside the Kabul airport, but they're not the only terrorists in the area.
"How real is this ISIS threat?" CNN's Brianna Keillor asked Sullivan on "State of the Union."
"The threat is real. It is acute. It is persistent. And it is something that we are focused on with every tool in our arsenal," Sullivan said.
Our commanders on the ground have a wide variety of capabilities that they are using to defend the airfield against a potential terrorist attack. We are working hard with our intelligence community to try to isolate and determine where an attack might come from.
It is something that we are placing paramount priority on stopping or disrupting. And we will do everything that we can for as long as we are on the ground to keep that from happening. But we are taking it absolutely deadly seriously.
The U.S. is still coordinating the evacuation effort with the Taliban, and President Biden has said the evacuation deadline may be extended past August 31.
"There’s discussions going on among us and the military about extending," Biden said on Sunday. "Our hope is we will not have to extend, but there are going to be discussions, I suspect, on how far along we are in the process."
But complicating matters on Monday, a Taliban spokesman told Sky News that the August 31 deadline for a U.S. military withdrawal is "a red line."
"If the U.S. or U.K. were to seek additional time to continue evacuations, the answer is no. Or there would be consequences. It will create mistrust between us. If they are intent on continuing the occupation it will provoke a reaction," the spokesman was quoted as saying.
Sullivan said on Sunday, "We're engaging through military channels with the Taliban. The Taliban, obviously, to a considerable extent are integrated with the Haqqani Network.
"Our effort is with the Taliban military commanders currently in charge of security in Kabul, because they need to understand that Americans and those who have worked with us need safe passage to the airport. And if that passage is disrupted or operations are interfered with, the United States will deliver a swift and forceful response."
Sullivan, speaking about the Afghanistan evacuation effort on Sunday, said he could not give "a precise number," but he believes "several thousand Americans" still await removal from the country, with only eight days until the August 31 deadline.
Sullivan said some Americans do not inform the U.S. embassy when they arrive or depart the country, so the number is hard to pin down.
"And it's our responsibility to get them out. That is what we are in the process of doing right now. We are working hard to organize groups of Americans, to bring them on the air base, to get them on flights and get them out of the country."
Sullivan said U.S. officials are communicating with those Americans "by e-mail, by telephone, by text message. They have been very responsive. And, as I said before, this is an operational and logistical challenge in a risky and dynamic environment. But we are executing a plan to get those American citizens out of the country."
He said Americans waiting for evacuation should know, "We will be reaching out and contacting you. We have already spoken with nearly all of them over the past 24 or 48 hours. We will be making a plan for you to come to the airport."
"And we have secured the capacity to get large numbers of Americans safe passage through to the airport and onto the airfield. The goal here is to move people as rapidly and safely and efficiently as possible. That's what we're doing."