The city wants the Metro 4b line, which is in the process of project documentation, to eventually connect all three terminals of the Tan Son Nhat International Airport in HCMC and runs to Long Thanh being built in its neighboring province of Dong Nai.

The proposal for the metro link between the airports is contained in a proposal the city made for the national railway development plan for the next decade with vision until 2050.

The proposed route will also boost connectivity between the two localities and Thu Duc City, the new city within HCMC, the proposal says.

Under the current plan, Metro 4b will run underground with three stations for a total length of 3.2 kilometers, connecting the Gia Dinh Park in Phu Nhuan District with Lang Cha Ca intersection south of Tan Son Nhat in Tan Binh District.

Construction of the VND109 trillion ($4.6 billion) first phase of Long Thanh International Airport began earlier this year. The first phase is set to be completed by 2025, giving the new airport a capacity of 25 million passengers a year.