Japan plans to provide long-term support to maritime authorities in the Philippines, Indonesia, Malaysia and Vietnam. The move is aimed at countering China's growing assertiveness in the South China Sea.

NHK has learned that the Japan International Cooperation Agency will develop a 10-year plan to support the four nations, which the government regards as top priorities in terms of security.

On-site surveys were conducted last month in the Philippines and Indonesia. Similar activities are scheduled for around April in Malaysia and Vietnam.

Japanese officials will discuss the provision of drones, radar systems and patrol boats with each country, and also the development of human resources.

A detailed plan is due by March next year.

China claims the rights to control almost all of the South China Sea.

Beijing enacted a law allowing the Chinese Coast Guard to use force in the region three years ago, and other countries are on high alert.

An expert on China at the Japanese Defense Ministry's National Institute for Defense Studies Iida Masafumi says boosting the four nations' maritime security capabilities will greatly help them to counter China.