The warning was issued by Prime Minister Nguyen Xuan Phuc last Friday, three months after the Communist Party Central Committee had issued an official warning against Ninh and requested that the government impose further punishment.

Vietnam's Communist Party has four modes of punishment against members: reprimand, warning, demotion and expulsion. The government has a similar four-tier punishment structure, with the last one being dismissal from service.

Ninh, 64, was found to have committed violations involved in wrongful divestment at Nha Trang Port JSC in the central province of Khanh Hoa and privatization at Vietnam Airports Corporation.

He also violated regulations in approving in principle the equitization and state capital divestment at the ports of Quy Nhon in south central Vietnam and Quang Ninh in the north.

Inpectors concluded Ninh had shown irresponsibility in leading, managing, inspecting and supervising, resulting in huge losses of state assets during the period he held positions as Secretary of the Ministry of Finance's Party Commission, Minister of Finance and the Vietnam Social Security's board chairman between June 2006 and 2011.

His mismanagement allowed two former general directors of Vietnam Social Security to commit violations in lending VND1.01 trillion ($43 million) to the Agribank Financial Leasing Company No 2 (ALC II), a state-owned finance leasing firm, in 2008 and 2009. By law, the agency is only allowed to lend money to state-run commercial banks. The two were tried, found guilty and received prison sentences last September.

Le Bach Hong, also a former Deputy Minister of Labor, Invalids and Social Affairs, got six years in jail while the other, Nguyen Huy Ban, was jailed for 14 years for their crime of "deliberate violations of state economic management regulations, causing serious consequences."

ALC II was declared bankrupt in December 2016. Its debt plus interest has now amounted to VND1.7 trillion ($73.32 million).

Ninh's violations were serious, causing huge losses to the state budget and badly affecting the reputation of the Communist Party, the Politburo said.

A sweeping corruption crackdown spearheaded by Trong has snared scores of high-profile officials over the last three years, especially in the energy and banking sectors. Last year, a large number of officials and businesspeople were prosecuted for corruption.