By Laurie Chen, Kiyoshi Takenaka and Sakura Murakami

BEIJING/TOKYO (Reuters) – Japanese Foreign Minister Yoshimasa Hayashi met his Chinese counterpart on Sunday and urged Beijing to promptly release a detained Japanese national.

Hayashi’s meeting with Qin Gang was the first visit to Beijing for a Japanese foreign minister in over three years, as the two rival Asian powers seek common ground amid rising regional tension.

An employee of Astellas Pharma Inc was detained in China for unknown reasons, a company spokesperson said a week ago. Five Japanese nationals are currently detained in China, two of whom have already been tried and found guilty, according to Japan’s foreign ministry.

“I made a protest against the recent detention of a Japanese person in Beijing, and made a strong point of our position on the matter, including the early release of this national,” Hayashi told reporters.

Qin responded that China “will handle (the case) according to the law”, according to a readout from the Chinese foreign ministry.

Hayashi said Japan is seeking transparency over the legal process regarding detentions and has asked for China to secure a fair and safe business environment. He did not elaborate on China’s reaction.

“This happened when the Chinese government is trying to promote Japanese investment to China, and we see a discrepancy there,” deputy press secretary of Japan’s Foreign Ministry Yukiko Okano said to reporters on Sunday, adding that this point was raised by Hayashi during his meetings in Beijing.

The Japanese minister also conveyed Tokyo’s grave concerns over an increase of China’s military activity, including its collaboration with Russia and its maritime presence in the East China Sea, he said.

“We both affirmed the importance of continuing to have a dialogue on issues including national security,” Hayashi said.

Hayashi said he spoke to Qin about the “importance of ensuring peace and stability in the Taiwan strait”. Beijing said Qin warned Japan “not to interfere in the Taiwan issue or undermine China’s sovereignty in any form”, stressing that Taiwan is “the core of China’s core interests”.

“Japan’s position has not changed, not with this remark, and not in recent years,” Okano said when asked for comment on Beijing’s account.

Tension has been rising over Taiwan, which Beijing claims as its own territory. China has never renounced the use of force to bring Taiwan under its control. The democratically elected government in Taipei rejects Beijing’s claims and says only its people can decide its future.

Japan also lodged a diplomatic complaint in August after five ballistic missiles launched by the Chinese military fell into Japan’s exclusive economic zone, near disputed islands known as the Senkaku in Japan and the Diaoyu in China.

After Tokyo on Friday announced export restrictions on semiconductor manufacturing equipment, following the U.S., Qin warned his counterpart “not to play accomplice to an evildoer”.

The curbs are aligned with similar measures from the U.S. and the Netherlands, aimed at restricting China’s ability to make advanced chips.

Hayashi told reporters the restrictions “are not aimed at any specific country”.

Despite their differences, China and Japan agreed to restart trilateral talks with South Korea, Hayashi said, calling the agreement “an important achievement” from his meeting with Qin.

“We agreed to continue communicating closely on various levels, including the foreign ministerial and leadership levels,” Hayashi added.

Japanese Prime Minister Fumio Kishida and Chinese President Xi Jinping met on the sidelines of the Asia-Pacific Economic Cooperation (APEC) summit in November, the first bilateral summit in almost three years.

(Reporting by Sakura Murakami and Kiyoshi Takenaka in Tokyo, and Laurie Chen in Beijing; Editing by Christopher Cushing and William Mallard)

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