President Park Geun-hye and U.S. President Barack Obama met Tuesday on the sidelines of the APEC summit in Beijing. It was the fourth summit between the two leaders.

During the 20-minute meeting, which took place following a working lunch of APEC leaders, Park and Obama pledged to make joint efforts toward the denuclearization of North Korea, according to a Blue House official. The two leaders also exchanged opinions on the need for cooperation among Korea, the U.S. and Japan, according to the official. No further details of the meeting were given.

Although the Blue House and the Foreign Ministry announced right before Park’s departure for Beijing on Sunday that a Korea-U.S. summit was likely to take place Tuesday, the exact time was still being worked out on the day the summit was to take place. It was such an aberration from the usual diplomatic practice that it raised doubts of a summit taking place at all.

As this would have been the first meeting between the two since the announcement of the delay of wartime operational control transfer and the release of two Americans detained by North Korea, the Blue House understandably wanted to confirm the U.S.’ position on how things stood between the two allies through a summit.

The Blue House may have also have felt the need to exercise “balance” in diplomacy through a summit with Obama. During the earlier summit meeting between Park and Chinese President Xi Jinping, the two sides announced the Korea-China FTA, as well as agreeing to step up efforts toward North Korean denuclearization.

Diplomatic observers suggest that Washington may have been cool to the idea of a Park-Obama summit. They note that the U.S. may not be too pleased with Korea’s active support of the China-led Free Trade Area of the Asia-Pacific initiative expressed during the Park-Xi summit.

Furthermore, there are concerns that Park’s continued rebuff of Japanese Prime Minister Shinzo Abe’s offers of a summit may not be appreciated by Washington, which has been pushing for Korea and Japan to improve ties. Indeed that point may have been raised during Tuesday’s summit meeting when the two leaders were said to have discussed the need for trilateral cooperation.

While the Blue House said there was sufficient time to hold “beneficial discussions,” the 20-minute summit ― about 10 minutes when taking into account the time taken up by interpretations ― could hardly have afforded an opportunity to discuss anything in depth.

The Northeast Asian region is in flux, with strategic interests of Korea, the U.S., China and Japan crossing at different points. While Korea does not need to be anxious about every move these players make, it should have a grand vision, a master plan, to guide its diplomacy.