The United States has reached a temporary ceasefire agreement with Taliban insurgents as the two sides negotiate a truce in Afghanistan, US Secretary of Defense Mark Esper said Thursday.

The announcement came as NATO defense ministers met in Brussels and a day after Afghan President Ashraf Ghani reported “notable progress” in negotiations with the Islamist insurgents.

“The United States and the Taliban have negotiated a proposal for a seven-day reduction in violence,” Esper told reporters, dubbing his meetings with NATO colleagues “productive.”

Esper did not say when the partial truce would begin, but on Wednesday a Taliban official told AFP that the group would begin a “reduction of violence” on Friday.

Washington and Taliban fighters have been locked in grueling talks that have stretched over more than a year, seeking an end to what has already become America’s longest war.

Citing Afghan and US officials, the New York Times has reported that President Donald Trump had given conditional approval to a deal with the Taliban to allow him to start withdrawing US troops.