Japan’s Cabinet gave formal approval last Friday to lifting some of Tokyo’s unilateral sanctions on North Korea in what could be seen as a move to counter Chinese President Xi Jinping’s visit to Seoul, during which South Korea and China strengthened their joint stance against Japan’s revisionist moves.

The measure came in return for Pyongyang’s active reinvestigation of the abduction of Japanese citizens to the North in the 1970s and 1980s, including the launch of a special committee to investigate the fate of all Japanese abductees.

The unexpected warming in the testy ties between North Korea and Japan, which has not been affected by a recent series of missile and rocket launches by Pyongyang, comes at a time when both are faced with increasing diplomatic isolation in the region.

There is little possibility that Abe’s hawkish administration will improve ties with South Korea and China, which are angered and concerned about its attempts to expand Japan’s military role abroad and gloss over its pre-1945 wartime atrocities. It may be that Abe has no intention of trying to enhance relations with Seoul and Beijing, and just intends to focus on cooperation with the U.S. to keep China’s growing power in check.

North Korea remains frustrated with the principled stance of President Park Geun-hye’s government in Seoul. It also appears to have fallen out of favor with China, its only remaining major ally, which is displeased with the North’s unruly behavior and attaches more strategic importance to its partnership with the South.

Talking over lunch a day after holding a summit meeting Thursday, Park and Xi shared the concern that Japan’s lifting of certain sanctions on North Korea might hurt international coordination in getting the recalcitrant regime to abandon its nuclear arsenal. Their concern appeared to have fallen on deaf ears as Tokyo hit back at moves by Seoul and Beijing to forge a united front on historical matters involving Japan.

South Korean diplomatic strategists now face the dilemma of keeping Japan within the framework of international sanctions on North Korea while countering the Abe administration’s revisionist course of action. The U.S. has so far shown understanding of Tokyo’s approach toward Pyongyang, with a State Department spokesperson saying last week that Washington believes Japan is handling bilateral negotiations with the North in a “transparent manner.”

Japan has ostensibly taken the stance of comprehensively resolving the issues of Japanese abductees and North Korea’s nuclear program in coordination with the U.S. and South Korea. But it appears that Seoul officials are bracing for the possibility that easing sanctions will ultimately lead to a visit by Abe to Pyongyang, opening the way for the establishment of formal diplomatic ties between the two sides. Pyongyang also seems to be using the kidnapping issue to exploit or cut the fragile link in the trilateral alliance between the U.S., South Korea and Japan.

It has yet to be seen whether Abe will go so far as to decide to normalize relations with North Korea before the long-standing nuclear standoff is resolved. At least, he may regard playing with such possibility as an effective form of leverage against the strengthening partnership between Seoul and Beijing.

But Japan’s past history of aggression and colonization might end up haunting the normalization talks with North Korea. South Korea failed to clarify the coerciveness of the 1910 treaty on Japan’s annexation of the peninsula when they normalized ties in 1965 because of its need for economic assistance. The North, which has based the legitimacy of its oppressive regime on its founding leader Kim Il-sung’s alleged struggle against Japan’s colonial rule, would not have this option. What Pyongyang would have to do is to make Tokyo clearly recognize and apologize for its past wrongdoings.

In this vein, it does not make sense for North Korea to keep silent about the Abe administration’s attempt to shy away from Japan’s official responsibility for the wartime sexual enslavement of Korean women. Seoul may have to seek cooperation with Pyongyang in handling historical issues with Tokyo ahead of forging a united front with Beijing.