U.S. Deputy Secretary of State Richard Armitage says China's role is vital to resolving North Korea's nuclear standoff, adding that Washington and its allies must not let Pyongyang think they are getting "nervous."

Armitage told reporters in Tokyo Wednesday that he thinks the most effective way to deal with North Korea is close cooperation between the U.S. and its allies while keeping China well in the game.

The comments by the senior U.S. official come as North Korea's No. 2 leader, Kim Yong-nam, is scheduled to visit Beijing next week.

Armitage was in Tokyo for talks with Japanese officials on security matters and to attend an international donors' conference on Iraqi reconstruction.