Thomson Reuters Foundation

Catholic leaders are lending their support to protesters against a Chinese-backed dam project in Myanmar, adding pressure on the government to cancel the hydro-power dam in the country's north.

Ongoing protests have brought together Catholic priests and nuns with hundreds of protesters in Myitkyina city to demand an end to the controversial project that activists say will damage the environment and force thousands off the land.

The influential Archbishop of Yangon, Cardinal Charles Maung Bo, in a sharply worded statement, said the dam project on the Irrawaddy river was an "environmental disaster" that would also hurt prospects for peace in the restive region.

"Myitsone dam is a death sentence to the people of Myanmar," he said.

"This river is the most sacred symbol of our nation; she is not a commodity to be bartered. For a peaceful future, Myitsone dam must be stopped," he told the Thomson Reuters Foundation in emailed comments.

Myanmar angered China in 2011 when its former quasi-civilian government suspended the $US3.6 billion dam project amid environmental concerns.

The archbishop's message on the Myitsone project wields considerable influence, said Debbie Stothard, secretary general of the International Federation for Human Rights.

"The statement is significant," she said.

"While Catholics form a small percentage of the population, the cardinal's statements on social justice seem to have a resonance," she told the Thomson Reuters Foundation on Wednesday.

Dams in Southeast Asia have come under greater scrutiny after several recent disasters.

The collapse of a hydroelectric dam in Laos in July displaced thousands of people and killed at least 27.

In August, as many as 85 villages in central Myanmar flooded after a dam failed, unleashing waters that blocked a major highway and forced more than 63,000 people from their homes.

Last month, a top Myanmar investment official suggested downsizing or relocating the stalled Myitsone project because of problems including an earthquake fault line under the site, and a large catchment area affecting residents.

Thaung Tun, chairman of Myanmar's investment commission, said original plans for the dam had failed to consider the impact on the community and the environment.

For the ruling National League for Democracy, finding a solution is critical, as China is Myanmar's largest trade partner, and as party officials try to shore up popularity in ethnic minority areas ahead of the 2020 general election.