Washington (CNN) The Trump administration is expecting North Korea to return up to 200 sets of remains believed to be US servicemembers who died during the Korean War, according to four administration officials.

Planning is underway to receive the remains from North Korea in the coming days, although the actual transfer date and location have not been finalized, the officials say. They add that the administration is ready to receive the remains as early as this week if the North Koreans decide to move quickly.

President Donald Trump has held up North Korea's agreement to return the remains as one of the successes of his historic June 12 summit with Kim Jong Un in Singapore.

The Defense Department estimates there are up to 5,300 sets of US servicemember remains still somewhere in North Korea. A total of 7,697 personnel remain unaccounted for from the Korean War. Some are pilots who were shot down, some are ground troops, others may be those who died in prisoner of war camps.

North Koreans are telling the US that one forensic reason they believe the remains are those of Americans is that the bones resemble those of westerners more than Asians, an official said. The official added that the remains of other nationalities killed during the war could be included in returned remains.

Read More