Cambodian Royal Group and Chinese Hydrolancang International Energy on Monday signed a joint- venture agreement to build a 400-megawatt hydropower dam on Mekong tributary in Stung Treng province in northeastern part of Cambodia.

The agreement was signed between Cambodian telecoms tycoon Kith Meng, president of the Royal Group, and Huang Guang-ming, chairman of the Hydrolancang International Energy.

Kith Meng said that the investment for the dam on Sesan River in Stung Treng province's Sesan district was the first non- governmental, multi-lateral project with shareholders from China, Cambodia and Vietnam.

Vietnamese company involved in the project was not present at the signing ceremony on Monday.

Later, there was also a signing on the power purchase agreement between the project company and the Electricity of Cambodia.

The deal was signed between Kith Meng and Keo Rottanak, director general of the Electricity of Cambodia, under the witness of Cambodian Deputy Prime Minister and Finance Minister Keat Chhon.

Under the agreement, the dam developer will sell all electric power produced by the plant to the Electricity of Cambodia.

The Government of Cambodia approved the dam construction earlier this month. According to the government's statement, the dam development is under a joint venture among Cambodian, Vietnamese and Chinese firms with the total investment of about 781 million US dollars.

It said that the project is a concessional contract of a 45- year build-operate-transfer (BOT), of which, 5 years for construction and 40 years for operations.

It remains unknown when the construction will be started.

The statement said that when the project is operational, the government will earn tax revenue of 29.6 million US dollars a year.

Stung Treng province is situated in northeastern Cambodia, some 481 kilometers from Phnom Penh, the capital of Cambodia.