Major General Sung Thin Co, deputy commander of the 2nd Military Region, which covers the northwestern provinces that includes those bordering China such as Ha Giang, Lao Cai, Lai Chau, called for more attention to environmental issues in the border area.

Since China is at a higher altitude than Vietnam, most rivers and streams that cross the border between the two countries flow from that country into Vietnam, he said at a session with the legislative National Assembly in Hanoi on Thursday.

China has been investing in numerous economic and industrial zones and natural resource exploitation and processing operations, and establishing residential centers with high urbanization rates near the border, he said.

These developmental activities have resulted in consequences such as toxic waste and wastewater being dumped in rivers and streams which then flow into Vietnam, affecting its environment and people's health, he said.

He called on the government to study the problem and soon negotiate and sign with China an agreement on cross-border environment management and protection.

"The border is the nation's green lung and protects the environment and health of the Vietnamese."

He also raised the issue of the many hydropower dams that China has built upstream. While the United Nations' Water Convention says upstream countries must be responsible for coordinating water for downstream countries, China has often failed to do this and at times even discharged water from the dams without warning, he said.

"[I] request that the government and border provinces issue diplomatic notes asking China to compensate Vietnam if they cause damage, ensure compliance with the Water Convention and bilateral agreements."

Last Sunday floods in the Ka Long River, which flows from China into Quang Ninh Province, swept away a 21-year-old man while he was rowing a boat on the river.

The flooding also destroyed dozens of cargo boats and submerged many streets in Mong Cai.

According to local residents, besides heavy rain since the previous day, an unannounced dam discharge in China was also a cause of the floods.