North Korea accused the United States on Monday of ignoring its efforts to return remains of American soldiers who were killed in the Korean War in the 1950s and threatened to stop collecting and returning the bodies.

The North's military said it informed the U.S. twice this year of "a number of" remains of U.S. troops found during land realignment and farming preparations in 10 different locations. But the U.S. Defense Department has not offered a concrete response and asked the North to wait, it said.

"Though lots of U.S. remains are being dug out and scattered here and there in our country, our side will no longer be concerned about it," said a military statement carried by the official Korean Central News Agency.

The Korean War ended in a 1953 cease-fire that has never been replaced by a peace treaty — leaving the Korean peninsula technically still at war. About 8,000 U.S. servicemen are listed as missing from the conflict.

The U.S. and North Korea had previously been involved in a joint project to recover remains in the North, but the effort was halted in 2005 after Washington said security arrangements for its personnel were insufficient.

In late January, a Pentagon official said North Korea offered to consider allowing the U.S. back into the country to resume searching for remains.

Larry Greer, a spokesman for the POW-MIA office at the Pentagon, said at the time that the U.S. would weigh the offer.

On Monday, State Department spokesman P.J. Crowley told reporters that the administration of President Barack Obama has a strong interest in the recovery of U.S. remains.

But, he said, the United States doesn't think the issue should be linked to stalled international disarmament talks aimed at ending the North's nuclear weapons program. "The issue of remains is a humanitarian one, and we think it should be on a separate track," he said.

The North's statement Monday accused the U.S. of pushing to resolve even humanitarian issues like the return of war remains within the framework of six-nation nuclear talks Pyongyang quit last year.

"If thousands of U.S. remains buried in our country are washed off and lost due to the U.S. side's disregard, the U.S. side should be wholly responsible for the consequences as it has developed the humanitarian issue into a political problem," it said.

The statement said the North gave the notification to the U.S. through an American military delegate in South Korea on Jan. 27 and on Feb. 26. The North said it handed over several photos taken of remains as well as a dogtag bearing the name Philip W. Ackly and a service number.

David Oten, a spokesman for the U.S. military command in Seoul, said that the Jan. 27 meeting took place at the border village of Panmunjom at the North's request and the country conveyed its position on U.S. remains recovery.

North Korea's statement said the country has over the years handed over the remains of 229 American soldiers to the U.S. through 33 joint projects.