The Pentagon on Monday warned that there is still an "active threat" in Kabul that "remains high and remains real," while confirming that U.S. troops will leave Afghanistan by President Biden’s Aug. 31 deadline.

Biden, over the weekend, warned that another terrorist attack in Afghanistan is "highly likely" – a sentiment echoed by the Pentagon during a press briefing on Monday. 

PACE OF US EVACUATION FLIGHTS FROM AFGHANISTAN SLOWING ONE DAY BEFORE BIDEN'S DEADLINE: OFFICIALS

Pentagon spokesman John Kirby said that there is an "active threat in various ways that we have to be prepared for." 

Kirby added that the U.S. military has and "will continue to have and will maintain the capability to protect ourselves and defend ourselves as we complete the retrograde." 

"We are operating under the assumption that we need to be prepared for future potential threats," Kirby continued, saying that the "threat stream is still real, still active, and in many cases, is still specific." 

"The threat remains high and remains real," Kirby said, adding that U.S. military forces on the ground in Kabul have "worked out a very carefully coordinated method of safely completing this retrograde." 

When asked to detail that method, Kirby replied: "We are in a particularly dangerous time now, not that it hasn’t always been dangerous, but it is particularly dangerous now, and we are not going to detail every aspect of our troop protection … while we have troops in harms way and while we try to get people out of Afghanistan." 

With regard to ISIS-K, the group that claimed responsibility for the attack that killed 13 U.S. service members last week in a suicide bombing outside Hamid Karzai International Airport, Kirby said that the group poses a "dynamic, moving, fluid, quick" threat. 

The deadline for all U.S. troops and diplomats to be out of Afghanistan is 3:29 p.m. EST Tuesday – 11:59 p.m. local time in Kabul, U.S. defense officials told Fox News. It will mark the first time in nearly 20 years that no U.S. troops will be on the ground in Afghanistan.

According to the White House, on Sunday, a total of approximately 1,200 people were evacuated from Kabul. The White House said that evacuation was the result of 26 U.S. military flights, 26 C-17s, which carried approximately 1,200 evacuees, and two coalition flights, which carried 50 people.

The White House said Monday that since Aug. 14, when the mission began, the U.S. has evacuated and facilitated the evacuation of approximately 116,700 people. And since the end of July, the White House said the U.S. has relocated nearly 122,300 people from Afghanistan.

The president had authorized 6,000 U.S. troops to deploy to Afghanistan to assist in the evacuation mission, as the Taliban is pushing to restore the Islamic Emirate of Afghanistan – the formal name of the country under Taliban rule before militants were ousted by U.S.-led forces in the wake of the 9/11 attacks. The attacks on Sept. 11, 2001, were orchestrated by al Qaeda while it was being sheltered by the Taliban in Afghanistan.

BIDEN WARNS ANOTHER TERRORIST ATTACK IN AFGHANISTAN ‘HIGHLY LIKELY’ IN NEXT 24-36 HOURS

The Pentagon, on Monday, did not provide the current number of U.S. troops on the ground, but maintained that the withdrawal would take place as planned. 

As for the airport in Kabul where the U.S. military has been evacuating Americans and vulnerable Afghans, the Pentagon said it would "remain operational through our final flights." 

"What it looks like after we are gone, I would just point you to what the secretary of state said," Kirby said Monday, referring to the State Department’s statement signed by nearly 100 countries, as well as NATO and the European Union, said last week they had received "assurances" from the Taliban that people with travel documents will still be able to leave the country. 

The Taliban has said they will allow normal travel after the U.S. withdrawal is completed on Tuesday when they assume control of the airport.

CLICK HERE TO GET THE FOX NEWS APP

"This is not a U.S. military function, and not a U.S. military responsibility once we have completed the retrograde," Kirby said. 

Meanwhile, Kirby said Monday that the U.S. is actively engaged in its counterterrorism efforts and will "protect the American people from threats that could come from Afghanistan," while noting that there are also threats to the homeland from the Levant, North Africa, and more. 

"We have counterterrorism capabilities to thwart those threats as best we can," he said. 

Fox News' Lucas Tomlinson and Jennifer Griffin contributed to this report.