Most of the debts are owed by its subsidiaries and associated firms, and there is a risk they would be unable to pay them off, the Ministry of Finance said.

A Song Da official who asked not be named told VnExpress that the company has been struggling to sign new contracts, which has affected its recent results.

Its revenues fell by 35 percent in 2018 to VND6.3 trillion ($271.5 million), while profits plummeted by 40 percent to VND333 billion ($14.3 million).

The ministry said some projects that Song Da invested VND3.5 trillion ($150.9 million) in years ago have yet to fetch returns.

They include the Nam Chien Hydropower Plant in the northern Son La Province and the Viet Lao Power Jsc, which was established to create a power partnership between the governments of Vietnam and Laos.

One of Viet Lao Power’s projects, the Xekaman 3 Power Plant in Laos’ southeastern Sekong Province, stopped operating in December 2016 due to technical problems.

The project’s debt to equity ratio is now 3.75, implying great risks, the ministry said.

Song Da Corp was established by the government in 1961 and has since been the main builder of major power plants in Vietnam, including the 2,400 MW Son La Hydropower Plant in Son La Province, the largest in Southeast Asia.

The company sought to go private in 2018, but has been unable to find buyers despite organizing several auctions, and the state still owns over 99 percent.