Congress has called on Zalmai Khalilzad to explain the withdrawal of US troops from Afghanistan and the Afghan dialogue in Doha.
Khalilzad, a member of Congress, asked if there was any certainty that Afghanistan would not become a hub for al Qaeda and other terrorists after the US withdrawal.
In response, he said that under the Doha Accords, everything was conditional on the Taliban:
"As far as security is concerned, the Taliban have made several promises and if they do not fulfill them, we will not withdraw troops."
But US President Donald Trump told the 75th session of the UN General Assembly that his country was working to end the ongoing war in Afghanistan and would soon withdraw its troops.
President Trump's latest remarks coincide with inter-Afghan talks between the Afghan government and Taliban negotiators in Doha.
So far the two sides have not been able to agree on a modus operandi for the talks and therefore the main talks have not yet begun.