"(We) will continue to cooperate in construction of nuclear power and its safe operation."

Energy conservation and the environment are in focus in a spate of agreements between Beijing and Tokyo as Chinese Premier Wen Jiabao makes his first visit to Japan, whose fuel efficiency is the highest in the world.

Nuclear power is an increasingly attractive option for countries that depend on costly imported oil and gas, and those trying to slow global climate change by cutting their use of coal, the most dirtiest fuel.

Coal accounts for a large part of China's primary energy use.

The agreement may give Japanese companies access to China's emerging nuclear market as Beijing plans to spend about US$50 billion on building around 30 nuclear reactors by 2020.

Japan plans to add new nuclear power stations but at a much slower pace as it already has the world third-largest nuclear power generation capacity after the United States and France.

The joint statement does not mention natural gas fields at disputed waters in the East China Sea.

China and Japan, the world's second- and third-largest oil consumers, also agreed to cooperate on other energy-related measures including:

* Promotion of technologies for cleaner use of coal at coal-fired power plants

* Cooperation in development and use of renewable energy, such as solar power.

* Japan to send 300 people in the next three years to help train Chinese officials on energy-saving policies. * Both countries will meet in Beijing in September to hold a bilateral energy saving and environment forum.