Secretary of Defense Lloyd Austin and Joint Chiefs of Staff Chairman Gen. Mark Milley provided an update of the evacuation of American citizens and pledged to successfully evacuate all American citizens attempting to flee the war-torn region.

"Right now there are troops at-risk. We are the United States military, and we will successfully evacuate all American citizens who want to get out of Afghanistan," Milley said during a joint press conference with Austin. "They are our priority #1. In addition, we intend to evacuate those who have been supporting us for years, and we are not going to leave them behind. And we will get as many out as possible."

Nevertheless, Austin noted, "We don't have the capability to go out and collect large numbers of people."

DEFENSE OFFICIAL DURING SAIGON OPERATION SAYS PENTAGON 'NOT TRYING HARD ENOUGH' TO EVACUATE AFGHANS

Previously, officials have been hesitant to guarantee that all Americans who wish to leave would be evacuated if they were not out by the Aug 31 withdrawal deadline.

"We remain laser-focused right now on Hamid Karzai International Airport," Lloyd said, adding that 4,500 troops were in Kabul helping with evacuation efforts. 

"There have been no hostile interactions with the Taliban, and our lines of communication with Taliban commanders remain open as they should be," Austin said.

US COMMANDERS INTERACTING WITH TALIBAN LEADERS, 'NO THREAT' BY GROUP TO AIRPORT EVACUATION: PENTAGON

Austin declined to say whether or not American troops will be sent outside of the airport to gather American citizens who are being blocked en route to the airport by Taliban checkpoints. Milley suggested he had not been given orders to do so.

"The forces that we have are focused on the security of the airfield," Austin said. "We will continue to coordinate and de-conflict with the Taliban and make sure those people who need to get to the airfield have the right credentials to ensure passage. The Taliban has been checking those credentials and if they have them they have allowed them to pass.

CLICK HERE TO GET THE FOX NEWS APP

"It’s obvious we’re not close to where we want to be in terms of getting the numbers through," Austin said. "We’re gonna get everyone that we can possibly evacuate, evacuated and I’ll do that as long as we possibly can, until the clock runs out, or we run out of capability."

Austin said he was aware of reports of Afghan military planes being flown out of the country but that he did not have firm figures on how many or if the military would attempt to recover them.

Milley pushed back against criticism that the U.S. government should have seen the collapse of the Afghan Security Forces coming by saying he saw no indications that the force would collapse in just 11 days.

U.S. officials are privately warning that it will be "challenging" to meet President Biden's Aug. 31 deadline to withdraw U.S. troops from Afghanistan, as thousands continue pouring into the country to protect the airport and assist in the mission to evacuate thousands of American citizens and Afghan allies, Fox News has learned.

President Biden has authorized 6,000 U.S. troops to deploy to Afghanistan to assist in the evacuation mission, as the Taliban pushes to restore the Islamic Emirate of Afghanistan – the formal name of the country under the 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.

Lucas Y. Tomlinson and Brooke Singman contributed to this report