The southern city is in 65th place and Hanoi in 66th in the Smart City Index compiled by Swiss business school International Institute for Management Development and the Singapore University of Technology and Design.

They measured 102 cities around the world based on five criteria: health and safety, mobility, activities, opportunities, and governance that focuses on how citizens perceive the scope and impact of efforts to make their cities smart, balancing economic and technological aspects with humane dimensions.

Vietnam's two major cities trail Singapore (1st), Taipei (7th), Hong Kong (37th), and Seoul (47th).

But they rank above Kuala Lumpur (70th), Bangkok (75th), Jakarta (81st), and Manila (94th).

Singapore is the world's smartest city, performing well in how services are made available to its citizens and the impact of technologies on citizens' daily lives.

Zurich is second, followed by Oslo, Geneva, Copenhagen, Auckland, Taipei and Helsinki, Bilbao, and Dusseldorf.

The report said among the biggest challenges Hanoi and Saigon face are traffic congestion and air pollution.

The air quality in Hanoi has gone from bad to worse in recent weeks with the capital consistently topping the list of cities with the worst air quality in the world out of more than 10,000 monitored by the app IQAir AirVisual.

The city of 7.5 million has around seven million vehicles, with two million more coming in from other places. Needless to say, severe traffic congestion during rush hour has long been a problem.

HCMC, which has a population of 13 million, too has been struggling for years with traffic congestion.

The number of private vehicles has been increasing exponentially, and there are more than 825,000 cars and 8.1 million motorbikes in the city. Public transport plays a marginal role.

Countries bringing up the bottom of the list were Cape Town, Manila, Greece, Rio De Janeiro, Abuja, Bogota, Cairo, Nairobi, Rabat, and Lagos.