Japan's Foreign Minister Hayashi Yoshimasa has asked China to respond on a scientific basis to Japan's plan to release treated and diluted water into the ocean from the crippled Fukushima Daiichi nuclear power plant.

Hayashi made the request at a meeting with China's top diplomat Wang Yi in the Indonesian capital of Jakarta on Friday.

Hayashi said Japan-China relations have wide-ranging potential, but they are now at a crucial phase, facing a number of issues and serious concerns. He said Japan wants to build constructive and stable relations with China.

Hayashi explained the Japanese government's plan to discharge treated water from the Fukushima plant into the ocean after diluting it to bring down the tritium levels below government safety standards.

He quoted the International Atomic Energy Agency as saying in its report that the plan is consistent with international safety standards.

On Thursday, Wang expressed his objection to the plan, referring to the water as "contaminated."

Hayashi strongly urged China to take a scientific approach to the issue, and said Japan is ready to communicate with China from a scientific viewpoint.

Water used to cool molten nuclear fuel mixes with rain and groundwater, and has been accumulating at the plant. The water is treated to remove most radioactive substances, but still contains tritium.

The Japanese government plans to dilute the treated water to about one-seventh of the World Health Organization's guidelines for drinking water quality before releasing it into the sea.

Hayashi expressed grave concern over the situation in the East China Sea, where the Senkaku Islands are located, as well as the joint military activities that China and Russia are stepping up around Japan.

Japan controls the Senkaku Islands. China and Taiwan claim them. The Japanese government maintains the islands are an inherent part of Japan's territory.

Japan's foreign minister also stressed the importance of peace and stability in the Taiwan Strait.

He called for the early release of an employee of a Japanese drug maker and other Japanese nationals who have been detained by the Chinese authorities.

Hayashi and Wang agreed that the two countries will closely communicate at all levels, including at the leader and foreign minister levels.