Khalilzad had renewed talks with the Taliban earlier this month on steps that could lead to a ceasefire and a settlement of the 18-year-long war in Afghanistan.
“I met Talibs today, I expressed outrage about attack on Bagram,” Khalilzad wrote on Twitter, referring to the attack on Bagram air base on Wednesday which killed two people and injured more than 70 others.
“We’re taking a brief pause for them to consult their leadership on this essential topic,” he added.
Taliban spokesman Suhail Shaheen said Friday’s meeting was “very good and friendly”, Reuters reported.
“Both sides decided to resume the talks after a few days of break for consultation,” he added.
The assault on Bagram base came despite the resumption of talks between the US and the Taliban days before in Qatar, as the parties look for a path to reduce violence or even reach a ceasefire, allowing a gradual withdrawal of US and NATO troops from Afghanistan.
Peace negotiations began earlier this year, though US President Donald Trump unexpectedly suspended talks in September citing an attack in Kabul in which an American soldier was killed.
Tens of thousands of Afghan civilians, security officials and more than 2,400 American service members have been killed in the almost two-decade-old war.
There are currently about 13,000 US forces in Afghanistan as well as thousands of other NATO troops.
US officials have said American forces could drop to 8,600 and still carry out an effective, core counter-terrorism mission as well as some limited advising for Afghan forces.