The leaders of Japan and South Korea have met for trilateral discussions with U.S. President Barack Obama on the sidelines of the international nuclear conference in The Hague.
Before the meeting started Tuesday, Mr.Obama said deepening coordination among Washington, Tokyo and Seoul, including "military cooperation that includes joint exercises," is vital to dealing with North Korea.
"Over the last five years, close coordination between our three countries succeeded in changing the game with North Korea and our trilateral cooperation has sent a strong signal to Pyongyang that its provocations and threats will be met with a unified response, and that the U.S. commitment to the security of both Japan and the Republic of Korea is unwavering." he said.
South Korean President Park Geun-hye and Japanese Prime Minister Shinzo Abe both agreed that a united response is very important when dealing with the threat of North Korea's nuclear and missile programs.
Relations between the two U.S. allies have been strained in recent years and this was the first formal meeting between South Korea's president and Japan's prime minister.
The United States has been urging Tokyo and Seoul to reduce tensions over historical disputes and focus on issues of common interest, such as North Korea's nuclear program.
Sung-Yoon Lee, a Korean studies professor at the Fletcher School of Law and Diplomacy at Tufts University, says the U.S. is used to its role as peace broker between Seoul and Tokyo.
"Well, the United States has found itself once again in the role of trying to be an intermediary between its two allies in northeast Asia. And this is not a new role for the United States, even though it is frustrating for the U.S. This kind of role playing by the U.S., it goes back to the Korean War; the exigencies of the war in 1950 created the need for the United States to bring Japan and South Korea together."
Jang Yong-seok, senior researcher at Seoul National University's Institute for Peace and Unification Studies, describes the meeting in The Hague as a chance to improve cooperation on North Korea's nuclear program.
"There has been lack of coordination among South Korea, the U.S., and Japan on the North Korean nuclear issue as diplomatic efforts to resolve the issue are in a deadlock. This meeting will provide an opportunity to restore coordination and enhance cooperation among the three parties to resolve the nuclear issue."
Ben Rhodes, Mr. Obama's deputy national security adviser for strategic communications, told reporters Friday that this trilateral meeting would be an important session.
"We believe this is a very important message to show the United States aligned with our two most important allies in northeast Asia . It's a signal of our commitment to the security of northeast Asia and our belief that when the United States and our allies stand together, we are much stronger in the region and in the world."
Last week, South Korea said the talks Tuesday would not include the contentious issue of so-called "comfort women," who were used by Japan's military as sex slaves during World War II. Seoul said the two sides were in consultations over holding lower-level meetings on the issue.
President Park has repeatedly refused offers to hold a bilateral summit with Mr. Abe, citing Japan's refusal to apologize again for crimes committed during its colonization of Korea from 1910 to 1945, and Japan's use of Korean women as sex slaves.
Tokyo is pointing to numerous apologies the Japanese government has already made, and a 1965 agreement that normalized relations and included a large payment to Seoul.
South Korea, along with China, protested Mr. Abe's December visit to a controversial war shrine. It also criticized Japanese Chief Cabinet Secretary Yoshihide Suga in February when he said the government would re-examine the testimonies of former comfort women that were used as the basis of a 1993 apology.
Mr. Abe this month promised to honor Tokyo's previous apologies over its colonial past, including the 1993 statement by then-chief cabinet secretary Yohei Kono.
Kono gave a speech about his investigation of 16 comfort women. In the speech, he admitted that during World War II, Japan pressed many comfort women into service. He then expressed an apology and self-reflection. Since then, the speech has come to be known as the "Kono Statement."
(This report was produced in collaboration with the VOA Korean service.)