American security experts held unofficial "Track II" meetings in Berlin with North Koreans earlier this week, a U.S. think tank said, amid heightened tensions over Pyongyang's planned rocket launch following a nuclear test.

The meetings took place on Tuesday and Wednesday, and the U.S. participants included Joel Wit, editor of the North Korea-monitoring website 38 North, and Victor Cha, chief Korea analyst at the Center for Strategic and International Studies, according to an email to reporters from the Center for Strategic and International Studies.

"This was a private academic exchange to discuss the state of affairs in East Asian security," it said without providing further specifics, such as the identities of the North Korean participants.

Choe Son-hui, deputy director for North American affairs at Pyongyang's Foreign Ministry, could have attended the meetings.

Last week, Choe was seen in Beijing in what appeared to be a transit stop on a trip to another country, according to sources.

The already-high tensions on the Korean Peninsula in the wake of the North's Jan. 6 nuclear test rose even higher this week as Pyongyang unveiled its plan to carry out a long-range rocket launch between Monday and Feb. 25 in violation of U.N. resolutions.

North Korea says its rocket launches are aimed at putting satellites into orbit, claiming it has the right to the peaceful use of space. But Pyongyang is banned from such launches under U.N. Security Council resolutions as it has been accused of using them as a cover for testing intercontinental ballistic missiles. (Yonhap)