The pace of changing dynamics on the Korean peninsula has been nothing short of astounding. After North Korean leader Kim Jong-un seemed to open a diplomatic door during his New Year’s address earlier this year, stating an interest in participating in the Pyeongchang Winter Olympics, the pro-engagement government of South Korean President Moon Jae-in stridently pushed forward an ambitious diplomatic engagement strategy with Pyongyang. The result has been a flurry of summitry, including an inter-Korean meeting last month and a looming meeting between U.S. President Donald Trump and Kim, now slated for mid-June in Singapore. In addition, China has hosted Kim for two summit meetings in less than a month, marking his first trips outside of North Korea since assuming power. Russia and Japan are also probing summits with Kim, not wanting to be left out of the diplomatic flurry.

Indeed, developments on the Korean peninsula are now moving too fast for Tokyo’s liking, even though it has supported the pressure tactics that contributed to the current breakthrough. Over the past year, the administration of Japan’s Prime Minister Shinzo Abe has been the Trump Administration’s closet ally on North Korea, acting in lock-step with Washington through its support of a bolstered “maximum pressure” campaign. That policy—including a hard-hitting sanctions regime, increased deterrence activities, and a more credible threat of military force—has certainly created unease in Pyongyang. The sanctions are biting the North as never before, especially those implemented by China on sectors such as coal and textiles. It is also true that Kim is likely cautious about the volatility of the Trump White House and its seemingly casual rhetoric over the past year about the potential use of military force on the Korean peninsula. Pyongyang also was likely concerned about the new influx of hawks, such as new National Security Advisor John Bolton and Secretary of State Mike Pompeo, within Trump’s national security team.

But these explanations are insufficient and too U.S.-centric to explain why Kim is coming to the table. While the role of sanctions and particularly China’s tougher approach to Pyongyang have made an impact, the real drivers here are coming out of the Korean peninsula. The Moon Administration in South Korea has staked its legitimacy on an ambitious gamble that now is the right moment for inter-Korean engagement and peace talks. Kim has rhetorically confirmed he shares these intentions, even though his motivations are different. Peace talks are happening now because Pyongyang feels it has reached a critical stage in the development of its nuclear weapons program. Kim is now able to achieve what his father and grandfather always dreamed: to talk with the United States directly, nuclear weapons-state to nuclear weapons-state.

Unfortunately, this breakthrough constitutes a potential nightmare scenario for Tokyo. In the wake of swift changes on the peninsula, Japan has been forced to adjust to the embrace of high-level summitry. This has prompted a new, high-level diplomatic push on Japan’s part, with two main aims.

The first aim is to mitigate risks that these fast-moving developments would threaten Japan’s security interests, as seen in Abe’s summit with Trump at Mar-A-Lago in April and a host of shuttle-diplomacy efforts by Japan’s Foreign and Defense Ministers over the past few months. Abe is also looking to host a further discussion with Trump on the sidelines of the G7 Leaders’ Summit in Canada next month, just days before the Kim-Trump meeting in Singapore.

Tokyo’s principal concern—which it continues to telegraph to the Trump Administration at multiple levels—is that a “deal” should not be made with Kim if it only focuses narrowly on rolling back Pyongyang’s intercontinental ballistic missile (ICBM) program. Such an action might be tempting for Trump, who could try to frame it as a “win,” but it would serve to isolate Japan (and South Korea), who would continue to be threatened by Pyongyang’s cache of medium and intermediate range missiles that could be tipped with nuclear warheads. This move to “decouple” the United States from its East Asian allies has been a long-held strategy by Pyongyang, and Tokyo is wary of Trump falling into the trap. The Abe Administration has also emphasized the need to broaden talks beyond the nuclear weapons program to include the North’s stock of chemical and biological weapons. Finally, Japan remains concerned about the broken-record legacy of negotiations with the North over the past two decades and insists that the United States and its allies cannot repeat the mistakes of the past.

Japan has also taken this approach in talks with its East Asian neighbors, pushing for concrete measures from the North towards denuclearization. Earlier this month, Japan hosted a Trilateral Summit with Chinese Premier Li Keqiang and South Korean President Moon Jae-in. Abe took the opportunity to stress the need for “complete, verifiable and irreversible disarmament” of Pyongyang’s nuclear weapons program. Seoul and Beijing, however, balked at the idea of including that in a joint statement released at the end of the meeting, favoring the softer language of “complete denuclearization,” which aligns with the wording from the Panmunjom Declaration released after the inter-Korean summit and provides considerable wiggle room for Kim.

The second important aim for the Abe government is to resolve the long-standing issue of its abducted citizens. During the 1970s and 1980s, 17 Japanese nationals were allegedly kidnapped off the west coast of Japan and other areas around the world by North Korean agents and brought to live in North Korea. In 2002, after then-Prime Minister Junichiro Koizumi visited Pyongyang, five Japanese citizens were returned to much fanfare in Tokyo. The shine quickly wore off in Japan, however, when North Korea claimed that the remaining suspected abductees were dead, missing, or had never been taken to begin with. Koizumi visited North Korea once more in 2004, but Pyongyang insisted that the issue was closed. Abe, likewise, failed to break the stalemate during his first stint in office, from 2006 to 2007.

Despite deep reservations about North Korean pledges regarding denuclearization, Abe feels he has a unique opportunity now to pressure the Kim regime to address the abductions. Indeed, the Japanese government has found a receptive partner with the Trump Administration. Trump met with the families of the abductees during his trip to Japan last year, and also raised the issue during his address at the United Nations General Assembly. Abe also secured a commitment from Trump during their last meeting at Mar-a-Lago that the United States would directly address the issue during the summit with Kim.

Japan will continue to seek balance in its two-track approach with North Korea, focusing on the security risks and abductions issue over the coming months. The primary worry for Tokyo, heightened by rapid developments of late, is that its views may be marginalized in any diplomatic deal with the Kim regime. As the world gears up for all the inherent uncertainties of a Trump-Kim summit, expect the Abe government to pay a constant attention to alliance management, as it seeks to keep its voice heard.