Japan, America¡¯s closest ally in Asia, has been trying to send a message to U.S. presidential hopeful Donald Trump: don¡¯t try to strike any deal with China that could upend years of collective efforts to rein in Beijing and risk the region¡¯s fragile peace.

Tokyo has stepped up attempts to engage with people close to Trump in recent weeks, as the 77-year-old¡¯s victories in Republican primaries in Iowa and New Hampshire have seen him emerge in some polls as the front-runner in November¡¯s presidential election.

The outreach ¡ª detailed in interviews with six Japanese officials, much of it previously unreported ¡ª comes as Prime Minister Fumio Kishida prepares for an April state visit to the United States at U.S. President Joe Biden¡¯s invitation.

Japan¡¯s endeavors have included dispatching a senior ruling-party figure to try to meet Trump, and engagement by Japanese diplomats with think tanks and former U.S. officials aligned with Trump, three of the officials said.

One of Tokyo¡¯s key worries is that if Trump returns to power, he may seek some kind of trade or security deal between the world¡¯s top two economies that could undermine recent efforts by the Group of Seven wealthy nations to counter China, according to the six officials, who spoke on the condition of anonymity because of the issue¡¯s sensitivity.

Trump, who reached a trade agreement with Beijing in 2019 that later expired, has not mentioned any potential deal with China during his campaign for the 2024 nomination.

The Japanese officials said they had no specific knowledge of Trump¡¯s plans, but they based their concerns on his public comments and actions during his 2017-2021 term, in which he eschewed some multilateral cooperation, defended his relationships with authoritarian leaders such as China¡¯s Xi Jinping, and unsuccessfully sought a nuclear deal with North Korean leader Kim Jong Un.

Two Japanese Foreign Ministry officials said they fear that Trump may be prepared to weaken U.S. support for nearby Taiwan in pursuit of a deal with China. They said such a move could embolden Beijing, which claims Taiwan and has not ruled out seizing the island by force.

A Trump aide said that no recent meetings have taken place between Trump and Japanese officials. They would not comment further.

Asked in an interview with Fox News in July 2023 whether the U.S. should help defend Taiwan if it means going to war with China, Trump said: ¡°If I answer that question, it will put me in a very bad negotiating position. With that being said, Taiwan did take all of our chip business. We used to make our own chips. Now they¡¯re made in Taiwan.¡±

Tokyo also worries that Trump may again hit Japan...