President Joe Biden has promised to hunt down the jihadists behind an attack in Kabul that killed at least 90 people – including 13 US troops.
Mr. Biden warned the US would “not forgive” the perpetrators.
The twin blasts, claimed by a local branch of Islamic State (IS), tore through crowds of men, women, and children outside Kabul airport.
They were hoping to join the 100,000 people airlifted out of Afghanistan since it fell to Taliban militants.
There had been repeated warnings that an attack was likely, but it either did not reach or did not deter those waiting.
US troops in control of Kabul international airport have been facilitating the evacuation of foreign nationals and Afghans who had been working with foreign missions.
They have been aiming to complete this within a 31 August deadline for US forces to leave under an agreement with the Taliban.
A number of European countries have already announced the end of their evacuation plans. The UK said on Friday it would not be processing any more applications, acknowledging it was leaving people behind.
Speaking hours after Thursday’s attack, Mr. Biden vowed to complete the evacuation mission, adding “we will not be deterred by terrorists”.