A U.S. government official has called on Tokyo to provide Washington with more details about bilateral talks held with North Korea.

State Department spokeswoman Jen Psaki told reporters Monday the U.S. government supports Japanese efforts to resolve outstanding issues with North Korea, including Pyongyang's past abductions of Japanese nationals, "in a transparent manner."

She made the remarks after Japan and North Korea held informal intergovernmental talks Monday in Shenyang, China, on the sidelines of their Red Cross talks over the retrieval of the remains of Japanese who died around the end of World War II in what is now North Korea.

"We're not opposed to remains recovery operations as a humanitarian effort," the spokeswoman said, declining to comment on the Japan-North Korea talks.

Psaki's comment apparently reflected general concerns in the U.S government about Tokyo's failure to share with Washington information about talks with the North.

U.S. officials were reportedly dissatisfied with a lack of information when Japan apparently held secret bilateral talks with North Korea in January in Hanoi. Japan notified the United States of the latest Red Cross talks in advance.