Japanese politician Natsuo Yamaguchi postponed a trip to Beijing at the request of the Chinese, the first tangible casualty of China’s unhappiness with Japan’s decision to release treated wastewater from the wrecked Fukushima nuclear power plant.

Yamaguchi, leader of the junior party in Japan’s ruling coalition, had been planning to visit China next Monday through Wednesday. On Saturday, the Chinese side told his party that “considering the current situation in Japan-China relations, it wasn’t the appropriate time to visit,” according to a statement from his Komeito Party issued Saturday afternoon.

Earlier this week China suspended all seafood imports from Japan in reaction to the Tokyo Electric Power Co. starting the release of the wastewater. That decision led to a wave of anti-Japanese anger online in China, prompting the Japanese consulate in Shanghai and embassy in Beijing to put out statements warning citizens to avoid speaking Japanese too loudly in public.

The Fukushima release is the latest in a string of issues which have plagued the Japan-China relationship in recent years, including a territorial dispute in the East China Sea and China’s increasingly assertive military exercises around Taiwan. China has been critical of Japan’s decision to limit exports of machines to make semiconductors and a recent agreement between Tokyo, Seoul and Washington, which it sees as part of US efforts to harm China.

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The Komeito has long had good relations with the Chinese government and has served as a conduit for talks during previous periods of poor bilateral relations. According to Japanese media, Yamaguchi was planning to carry a letter from Prime Minister Fumio Kishida to Chinese President Xi Jinping.

--With assistance from Takashi Hirokawa.