Donald Trump and Kim Jong Un
Donald Trump and Kim Jong UnReuters

A U.S. military plane left North Korea on Thursday carrying the remains of U.S. troops killed decades ago in the Korean War, the White House confirmed.

The Air Force C-17 aircraft left the city of Wonsan and is en route to Osan Air Base in South Korea, located roughly 43 miles south of Seoul, said White House press secretary Sarah Huckabee Sanders said.

Once the remains arrive in South Korea, a formal repatriation ceremony will be held on August 1, according to The Hill.

It was not immediately clear how many remains had been handed over to the U.S. The official South Korean Yonhap news agency reported that it was about 50.

The repatriation of the remains comes as part of a deal struck by President Donald Trump and North Korean leader Kim Jong Un during their summit in Singapore last month.

While the fighting in the Korean War lasted from 1950 until 1953, the war never formally ended, because a treaty was never signed. There about an estimated 5,300 Americans who did not return home from the conflict.

CNN had reported on Tuesday that the U.S. had not yet received confirmation from the North that the remains would be returned, and that Pyongyang had not given either the U.S. or South Korea the go-ahead for the transfer.

Yonhap reported Thursday that the North would begin returning the remains.

The deal between Trump and Kim also includes a commitment to achieve total denuclearization of Korea, with promises to pursue “vigorous negotiations” to that end.

Subsequent reports suggested that despite its commitment to denuclearize, North Korea has continued to expand infrastructure at nuclear and missile sites.

This week new satellite imagery was released of North Korea’s main satellite launch facility, the Sohae Satellite Launching Station, indicating that the North has begun dismantling key facilities.