Taiwan and China have agreed to cooperate more closely on nuclear power safety and disaster preparedness in the wake of Japan's atomic crisis this year, Taipei authorities said Wednesday.

The two sides will sign an agreement at the upcoming round of talks between their top negotiators on October 20 in the northern Chinese city of Tianjin, said Taiwan's semi-official Straits Exchange Foundation.

Under the deal, Taiwan's Atomic Energy Council and its Chinese counterpart would alert each other if disaster struck and cooperate to limit the damage, Taipei officials said.

Such a deal is needed because the majority of mainland China's nuclear facilities are on its southeast coast, only 100-200 kilometres (62-124 miles) from the island, officials said.

China has previously announced plans for more than 20 new plants.

However, the foundation said they were still negotiating with Beijing on a more complex investment protection pact, which the two sides initially hoped to sign last year but had to put off as they failed to agree.

Taiwan has been a major investor in China in recent years, providing more than $100 billion in financing, according to some estimates, as well as crucial technological know-how.

Taiwan and China have been governed separately since the end of a civil war in 1949, but Beijing still considers the island part of its territory and has vowed to bring about reunification even if it means war.

Despite this underlying tension, and a continued Chinese military build-up, the two sides have seen significant progress since 2008 after China-friendly Ma Ying-jeou became Taiwan's president.

A 9.0-magnitude earthquake on March 11 triggered a vast tsunami in Japan which crippled cooling systems at a nuclear plant, causing meltdowns and radiation leaks that forced tens of thousands of people to evacuate their homes.