South Korea on Thursday agreed to return the remains of 425 Chinese troops killed during the 1950-53 Korean War to their homeland, a decision that could help ease diplomatic tension caused by their overlapping air defense zones.

In June, President Park Geun-hye offered to send the remains back to China during her talks with Chinese Vice Premier Liu Yandong in Beijing.

“The two countries agreed on the return of the remains following a series of working-level consultations. We decided to hand over the remains excavated so far as soon as possible,” a Defense Ministry official said, declining to be named.

“The repatriation would be a crucial milestone in the development of the bilateral relationship.”

The remains of Chinese troops are currently interred at the cemetery of enemy forces in Paju, Gyeonggi Province.

Officials said it would take several months to finish the excavation work and the process of cleaning the remains. The repatriation process will be led by the Chinese side with support from the Korean government, officials said.

In addition to the remains of the deceased, the Defense Ministry agency in charge of the recovery and identification of the remains has collected their fountain pens, military badges, seals and other belongings.

Upholding the Geneva Conventions on the humanitarian treatment of prisoners of war and deceased troops, the Seoul government established the cemetery for North Korean and Chinese soldiers in Paju in 1996 after consolidating the graves then scattered across the country.

The cemetery also holds the remains of some 718 North Korean soldiers, including the 30 North Korean guerillas killed during an infiltration of the South in an attempted attack on Cheong Wa Dae in 1968; a North Korean terrorist who killed himself after bombing a South Korean flight in 1987; and six North Korean spies who were shot to death during a failed south coast infiltration in 1998.

Diplomatic tension between South Korea and China sharply increased last month after Beijing announced a new air defense identification zone that overlapped with South Korea’s.

The unilateral move unnerved the Seoul government as it has sought to improve ties with China, its largest trading partner and host of the multilateral talks aimed at Pyongyang’s denuclearization.

By Song Sang-ho (sshluck@heraldcorp.com)