The remains belong to Chinese soldiers who died fighting against South Korea in the 1950-53 Korean War. China fought alongside North Korea, while the South was backed by UN forces including US troops.

"Historically, the repatriation of soldiers' remains between former war adversaries carries a peaceful message to heal the wounds of the past and develop their relations," Hwang In-moo, South Korea's vice defense minister, said in a speech at the event.

Seoul and Beijing struck an agreement in 2014 on the return of Chinese soldiers' remains excavated from graves in South Korea on the basis of the humanitarian spirit specified in the Geneva Conventions.

Hwang called it "proof of trust" between the two sides.

China expressed its gratitude to the South Korean government and its people.

"(We) appreciate the friendship and good will that South Korean people and media have shown regarding the repatriation of Chinese soldiers' remains," said Sun Shaocheng, China's vice minister of civil affairs, leading his country's delegation.

More than 180,000 Chinese soldiers are estimated to have died in the war.

A total of 541 remains were sent back in three batches as of last year.

There had been some doubts about the implementation of the deal, with the two sides at odds over the deployment of a Terminal High Altitude Area Defense battery to South Korea.

China believes the US is seeking to position the advanced missile defense system on the peninsula not only to help ward off North Korea's threats but also to counter Beijing's growing military influence in the region.

The allies, however, stress the need for the THAAD unit here is solely to cope with the North's possible missile attack more effectively.

"Although there is a difficulty in South Korea-China relations in the process of resolving the North Korean nuclear and missile issue, we pushed for the repatriation of the remains of Chinese soldiers this year from the humanitarian perspective," the ministry said in a separate statement.

It vowed to continue the program and efforts to improve bilateral ties.

Both Hwang and Sun did not mention the THAAD issue in their brief public remarks. (Yonhap)