The U.S. is already cutting down the number of troops it has stationed in Afghanistan, according to the commanding officer of NATO’s Resolute Support Mission and US Forces - Afghanistan.

Army Gen. Austin Miller said Monday approximately 2,000 U.S. troops had left Afghanistan in the past year, the New York Times reports. That means there are approximately 12,000 U.S. troops remaining in Afghanistan — a decrease from the roughly 14,000 that were previously stationed there.

The decrease is not connected to a formal withdrawal order, but instead is occurring as troops wrap up their tours in Afghanistan. Those troops leaving the country are then never replaced, U.S. and Afghan officials told the New York Times.

Officials did not disclose further information, however, the New York Times reports that an Afghan official approved the move.

Miller’s remarks come days after Secretary of Defense Mark Esper told reporters traveling with him to Afghanistan on Saturday that a withdrawal of U.S. troops in Afghanistan would be “conditions based.” However, he said the U.S. believes only 8,600 troops are necessary to keep up current counter-terrorism operations.

“With regard to a withdraw of forces, as we've always said, that it'll be conditions based, but we're confident that we can go down to 8,600 without affecting our [counter-terrorism] operations, if you will,” Esper said.

“​But all that — again, we think a political agreement is always the best way forward with regard to next steps in Afghanistan,” Esper added.

When pressed whether the troop reduction would happen with or without a peace deal with the Taliban, Esper said he didn’t “want to get ahead of the diplomats on that front.”

Peace negotiations with the Taliban crumbled in September after a secret meeting with Taliban and Afghan leaders at Camp David was canceled. President Donald Trump said that he called off the meeting after a U.S. soldier and 11 others were killed in a Taliban car bomb attack.

Before the peace negotiations were dismantled, U.S. Special Representative for Afghanistan Reconciliation Zalmay Khalilzad shared a draft of the U.S.-Taliban agreement with Afghan leaders. The plan would have required the U.S. to withdraw approximately 5,000 U.S. troops in Afghanistan 135 days after signing the agreement, according to the Associated Press.

The U.S. has had troops in Afghanistan since Oct. 2001 because the Taliban provided a safe haven for al-Qaida leader Osama bin Laden.