Senior U.S. diplomat Kurt Campbell has arrived in China, the first stop on a four-day tour that will also take him to South Korea and Japan.

Campbell, the assistant Secretary of State for East Asian and Pacific affairs, made no comments on arrival at the airport in Beijing Tuesday, but the State Department had said earlier that he will discuss “a range of important bilateral, regional and global issues, including the latest developments related to North Korea.

The three Asian countries are also close neighbors of nuclear-armed North Korea.

Campbell is the highest-level U.S. official to visit the region since the death of North Korean leader Kim Jong Il. The United States, China, South Korea and Japan are parties in the stalled six-nation talks on North Korea's nuclear disarmament. Russia also is part of the talks.

Campbell's trip ends January 7.

The six-nation nuclear talks are aimed at convincing North Korea to abandon its nuclear program in exchange for massive economic aid. Pyongyang walked away from the talks in April 2009, but signaled last year that it would like the talks to resume.

One of the obstacles to the resumption of the talks is the continuing tension between the two Koreas, that are technically still at war.

On Monday, South Korean President Lee Myung-bak expressed optimism that this year could be a turning point in the North Korean nuclear dispute. He said that Seoul was ready to resume six-party talks and provide economic assistance to the North, if Pyongyang agrees to suspend its nuclear activities.