Radio Free Asia says that South Korea and the United States prepared joint measures against a North Korean contingency in August.

Citing diplomatic sources in Washington, the broacaster reported Friday that the two sides discussed basic principles and cooperation measures in case of a contingency in North Korea, such as leader Kim Jong-il's death or a power transfer. The closed-door meeting was held at the East-West Center in Hawaii last month.

Radio Free Asia said 12 officials from each side attended the meeting headed by South Korean nuclear envoy Wi Sung-lac and U.S. chief delegate to the six-way talks Sung Kim.

A source said the two sides agreed that South Korea will take the initiative in such situations and the U.S. will cooperate with the South to build a free, democratic and unified Korea.

They also reportedly agreed to swiftly control weapons of mass destruction, including nuclear weapons, on the Korean Peninsula and block any military provocation against South Korea.