The inauguration of a new South Korean administration this month will bring Tokyo, Seoul and Washington closer to a unified position on how to deal with North Korea, while Japan's concerns that it might be left behind by the U.S. diminish as Pyongyang delays disclosing its nuclear programs, experts and government officials say.

"The change of government in South Korea will have a positive impact" on Japan and the six-party talks on North Korea's nuclear ambitions, said Hitoshi Tanaka, a former diplomat and now a senior fellow at the nonprofit think tank Japan Center for International Exchange. Tanaka was Japan's top negotiator with the North and engineered the historic September 2002 Pyongyang summit between Prime Minister Junichiro Koizumi and Kim Jong Il.

Lee Myung Bak, who on Feb. 25 will take over as president of South Korea, has promised to improve ties with Japan and the U.S., which have been strained under Roh Moo Hyun, and to review Seoul's policies on North Korea and take a more hardline position than previous administrations.