Phong said the city has made a proposal to increase investment in Metro Lines 1 and 2 and needs to complete documents for submission to the municipal People's Council by October 21. However the Ministry of Planning and Investment and the Ministry of Finance have remained silent so far.

If all the administrative work is not finished by next month, contractors who have not been paid are likely to stop work on Metro Line 1 and this could result in legal issues, he said, adding that Metro Line 2 could also lose its funding as a result.

The delays in the two metro lines could affect the relationship between Vietnam and the countries that have provided official development assistance (ODA) loans for the projects, and could lower Vietnam’s possibility of acquiring loans in the future, Phong said.

Local and international observers could form negative opinions about the implementation of ODA-funded projects in Vietnam, he added.

HCMC’s Metro Line 1, or Ben Thanh-Suoi Tien metro, is to run nearly 20 kilometers (12 miles) through the city’s 1, 2, 9, Binh Thanh and Thu Duc districts, and the neighboring Binh Duong Province's Di An District.

It is now 67 percent complete and expected to begin operations in April 2021.

The project was first approved in 2007 at a cost of VND17.4 trillion ($750 million). Later, in 2010, a proposal was made to triple the investment to VND47 trillion ($2 billion). However, the proposal has not been approved.

Metro Line 2, or Ben Thanh-Tham Luong, has seen its proposed cost almost double from VND26 trillion ($1.1 billion) to VND48 trillion ($2 billion). Completion time has been rescheduled from 2024 to 2026 because of prolonged administrative delays.

Only an administrative building as part of the project has been finished. When completed, the metro will run 11.3 kilometers (7 miles) through districts 1, 3 10, 12, Tan Binh and Tan Phu, mostly underground.