The trial call, made publicly with the participation of the Ministry of Information and Communications, showed that the speed of Viettel's 5G mobile network connections reached 1.5-1.7 Gigabits per second, far exceeding the theoretical limit of the 4G network and equivalent to the speed of optical cable.

Viettel said it will expand the test to Hanoi and Ho Chi Minh City, the nation’s two biggest cities, and expects to launch the commercial service in 2020.

The military-run company said it is looking at many pricing plans for commercial 5G services.

Minister of Information and Communications Nguyen Manh Hung, who led Viettel earlier, said the event marked Vietnam as one of the earliest nations in the world to successfully test the 5G network, after the U.S., Australia, Japan and South Korea.

"We all want to take the lead in the fourth industrial revolution and develop information and communications technology so that Vietnamese locals and businesses can compete in the global economy, and therefore, the earlier we launch the 5G service, the better," he said.

Viettel became the first firm to receive permission to trial 5G services in January. It was followed by MobiFone.

Last November, Hung said at a conference that Vietnam should test 5G in 2019 and ensure nationwide coverage by 2020.

"Vietnam should be one of the first countries to launch the network, at least in Hanoi and HCMC," he had said. The country had been one of the last in Southeast Asia to roll out 4G services.

5G is the latest generation of mobile Internet connectivity, and should offer much faster speeds and more reliable connections on smartphones and other devices compared to the current 3G and 4G technologies.