TOKYO (Kyodo) -- The Japanese government did not approve a visit by former Taiwan President Tsai Ing-wen last July to attend a memorial service for former Japanese Prime Minister Shinzo Abe due to concerns over a backlash from China, sources familiar with the matter said Thursday.

The Japanese government, at the time led by Prime Minister Fumio Kishida, was working to lift China's ban on imports of Japanese seafood, imposed in the wake of the release into the sea of treated wastewater from the crippled Fukushima Daiichi nuclear power plant, and did not want to add to tensions, they said.

China views Taiwan, a self-ruled democratic island, as a renegade province awaiting reunification, by force if necessary. It has previously criticized Japan for allowing visits by former Taiwan President Lee Teng-hui, noting that Tokyo severed diplomatic ties with Taipei in 1972 and acknowledged Beijing's Communist-led government as China's "sole legal government" in a joint communique.

When Lee visited Japan for medical treatment in 2001, China reacted by postponing a visit by the chairman of the Standing Committee of the National People's Congress.

Abe, known for his conservative and hawkish security views, had built close ties with Taiwan, including with Tsai when she was serving as president, and continued to show support for the island even after he stepped down as prime minister in 2020.

Warning of the potential military threat posed by China, he said a contingency for Taiwan would be a contingency for Japan. Abe was gunned down during an election campaign speech in 2022.

The latest revelation may lead to criticism of the Japanese government for having shown excessive consideration to China.

Tsai's visit was arranged by a cross-party group of Japanese parliamentarians dedicated to strengthening Tokyo-Taipei relations, for which Abe served as an adviser.

During a delegation visit to Taiwan around the time of the presidential election in January last year, as well as on other occasions, the group repeatedly encouraged Tsai to visit Japan after she leaves office.

Tsai, who stepped down in May last year, planned to attend a memorial event in Tokyo for Abe in July that year, which would have marked her first post-retirement foreign trip.

The Japanese government, however, strongly urged ruling Liberal Democratic Party lawmaker Keiji Furuya, who heads the cross-party group, to call off the visit given that "Japan-China relations are at an important stage," according to the sources.

Tsai and Furuya agreed to rearrange the timing of her trip to Japan as a result, they said.

China imposed a blanket ban on Japanese seafood products immediately after Japan began discharging treated radioactive water from the Fukushima plant into the Pacific Ocean in August 2023.

In July last year, then Japanese Foreign Minister Yoko Kamikawa and her Chinese counterpart, Wang Yi, agreed to accelerate talks on the water discharge.

In September, the two countries said that China had agreed that seafood imports from Japan would gradually resume, contingent on Beijing's participation in activities to monitor the discharge.