WASHINGTON – President Joe Biden was warned Friday that another terrorist attack was “likely” in Kabul the day after a suicide bomber outside the city’s airport killed at least 113 people, including 13 US soldiers.

The sharp warning from the president’s national security team came as the United States entered the final days of a month-long military retreat from Afghanistan to meet Biden’s August 31 deadline for a full withdrawal.

In the two weeks since the fall of Kabul on August 15, the US and coalition partners have facilitated the evacuation of more than 100,000 people, including more than 5,000 American citizens. The Pentagon announced on Friday that more than 5,000 US soldiers are in Kabul to help with the evacuation effort.

CNBC policy

Read more about CNBC’s political coverage:

“The next few days of this mission will be the most dangerous time yet,” they told Biden, according to a White House statement.

In response, Biden reiterated his “approval of all authorities that need them to conduct the operation and protect our troops,” the White House said. The generals confirmed to the president that they had the resources they believed needed to be done effectively.

Marine Gen. Kenneth McKenzie, commander of U.S. Central Command, said Thursday that ISIS will likely attempt to continue the attacks before the evacuations are complete.

McKenzie, who oversees US military operations in the area, said threats against Western forces and civilians at the airport ranged from gunshots to missiles to suicide bombings.

“So, at any time, there can be very, very real streams of threats that we would call tactical and imminent,” he said.

Military commanders also briefed Biden and Vice President Kamala Harris on Friday of plans to develop targets under ISIS-K, the splinter group of Islamic militants who championed Thursday’s attack.

Biden alluded to these plans in his remarks on Thursday evening.

“We will not forgive. We will not forget. We will hunt you down and make you pay,” said Biden from the White House.

“We will find ways of our choosing, without major military operations, to get them wherever they are.”

– CNBC’s Amanda Macias contributed to this report.