US envoy Zalmay Khalilzad. File photo

Afghanistan's government is expressing new concerns about a deal that a U.S. envoy says has been reached "in principle" with the Taliban on ending America's longest war.

A statement shared by presidential spokesman Sediq Seddiqi on Wednesday asks for clarifications about the agreement and its risks to avoid "unpleasant consequences."

The statement says the Afghan government shares the concerns raised by several former US ambassadors to Afghanistan.

On Tuesday, their joint statement warned that a full US troop withdrawal that moves too quickly and without requiring the Taliban to meet conditions, such as reducing violence, could lead to "total civil war."

US envoy Zalmay Khalilzad showed the draft of the deal to the Afghan president, Ashraf Ghani, earlier this week, saying it only needs President Donald Trump's approval.

Associated Press