U.S. President Barack Obama will meet with South Korean President Park Geun-hye and Japanese Prime Minister Shinzo Abe on Thursday to discuss North Korea's nuclear program, the White House said on Monday.
The meeting on the sidelines of the Nuclear Security Summit in Washington will take place the same day Obama talks with Chinese President Xi Jinping.
"This meeting will be an opportunity for the three leaders to discuss common responses to the threat posed by North Korea and to advance areas of trilateral security cooperation in the region and globally," the White House said in a statement.
Relations between Park and Abe have been frosty in the past, but the two have been brought together in recent months by shared concerns about North Korea, which conducted a fourth nuclear bomb test on Jan. 6 and launched a long-range rocket into space last month.
The United States has been keen to encourage better relations between Seoul and Japan, its two biggest allies in Asia, given concerns not only about North Korea but also an increasingly assertive China.
Beijing has said Xi will push Obama to resume talks on the North Korean nuclear issue. Their meeting could also touch on U.S. concerns about Chinese computer hacking and Beijing's assertive pursuit of territory in the South China Sea.
Obama, Park and Abe last met trilaterally on the sidelines of the previous Nuclear Security Summit in The Hague in 2014, but only at the cajoling of the U.S. president.
Last November, Abe and Park held their first formal bilateral talks since taking office and the following month Japan and South Korea reached a landmark agreement to resolve their long-running dispute over women forced to work in Japan's wartime brothels.
Military officials and defense officials said after the North Korean nuclear test in January that shared concerns about North Korea could cement the reconciliation and open the way for increased military cooperation between Japan and South Korea.
Washington is relying increasingly on its Asian allies to work together and says trilateral defense cooperation is critical to maintaining regional security.
China has signed up for tough new U.N. sanctions against North Korea but it has said repeatedly sanctions are not the answer and that only a resumption of talks can resolve the dispute over North Korea's weapons programme.
Numerous efforts to restart the talks have failed since they collapsed following the last round in 2008.