TOKYO (TR) – After taking office last year, Prime Minister Sanae Takaichi has raised tensions between Japan and China.
Seemingly undeterred by such a stance is Hideo Tarumi, a former ambassador to China. Known as a “hardliner against China,” the diplomat has developed an apparent double life that includes maintaining a Chinese mistress and her child, says weekly tabloid Shukan Post (Feb. 20).
Tarumi has a wife and children. But, according to the magazine, he visits the apartment of the woman from China on weekends and has built a relationship that seems like a second family.
Elegant features
On January 24, the day after Prime Minister Takaichi dissolved the House of Representatives, a light van was parked in front of an apartment building in central Tokyo at just after 8:00 p.m.
Thereafter, a pale, slender woman in her 40s with elegant features exited the passenger seat and entered a unit of the apartment building.
The car then pulled into a parking lot a short distance away, where a man wearing a dark, half-length down jacket and a commemorative cap for the Hanshin Tigers exited. The man warily peered into each parked car as he quickly made his way to the apartment building, unlocking the auto-lock door with his key before entering.
The next day, the man and woman went out together. They walked back to the parking area, where the man got into his car alone and headed home.
It has been confirmed that they also spent time together on the night of January 11 and in December.
“Most wary of”
The apartment is occupied by a woman from China and her child. The real estate registry confirms that the room is registered in a Chinese name. The man who visits the woman’s apartment on weekends is Tarumi.
Known as a hard-line diplomat on China, Tarumi has served as director of the China and Mongolia Division at the Ministry of Foreign Affairs and as envoy to China. He then serving as ambassador extraordinary and plenipotentiary to China from September 2020 to December 2023.
While serving as ambassador to China in August 2023, China suspended imports of Japanese seafood over the ocean release of treated water from the Fukushima Daiichi Nuclear Power Plant. They claimed that this was “an act of shifting the risk of nuclear contamination to neighboring countries and the international community.”
Tarumi retorted, “Measures that are not based on scientific evidence are unacceptable,” which earned him the reputation of “the diplomat China is most wary of.”
Bestseller
Since retiring from the ministry, Tarumi has continued to teach as a university professor. He has also made diplomatic recommendations to the government, which have drawn attention.
Among them was his essay “Prime Minister Takaichi’s China Strategy: Three Prescriptions” in the January 2026 issue of the monthly Bungeishunju. The essay was regarding the rising tensions in Japan-China relations following Prime Minister Takaichi’s controversial comments in the Diet last November. During the session, she said that China’s “use of force on Taiwan” could constitute a “survival-threatening situation” for Japan.
His book “Secret Records of Japan-China Diplomacy: The Struggle of Ambassador Hideo Tarumi to China,” published by Bungeishunju in June last year, became a bestseller.
“I have no idea what you are talking about”
When approached by the magazine about the woman, Tarumi denied knowing her. After being further pushed about their apparent relationship, he said, “Wait a moment. I’m a private citizen. Isn’t it illegal to investigate matters that pertain to a private citizen’s privacy?”
The reporter then asked whether he had been meeting her since his time as ambassador.
“I have no idea what you’re talking about,” Tarumi said. “How could I meet [someone] in China while I was ambassador? I have no idea what you’re talking about. Not only are you talking about my time as ambassador, but I’m a private citizen now. I don’t mind if you’re aware that discussing something that concerns your privacy is illegal, but I’m consulting with a lawyer, so that’s all I can say.”
The reporter then showed a photo of Tarumi that appeared to show him with the woman and her child. He said, “What’s that photo? I have no idea. Besides, we live in an age where you can make as many photos as you want.”
