A Grand Prix in Hanoi will be added to the Formula One calendar in 2020 as part of the sport's expansion in Asia.

F1 chairman Chase Carey and Nguyen Duc Chung, the Mayor of Hanoi, made the announcement on Wednesday.

A 5.556-kilometer circuit will be constructed near the national stadium using a combination of existing infrastructure and roads to be built in a new residential area on the edge of the city center.

"The race track in Hanoi is unique in the world with half of it being on existing streets and the other half to be built," Chung said. "The length and turns of this track will bring a lot of excitement. According to designers, it will be the most exciting track in the world."

Chung said the GP would be funded by private enterprise headed by Vingroup, the country's largest private conglomerate.

"Hosting Formula 1 races in Hanoi will open us many opportunities for business, tourist development (and) advertise the image of Vietnam and image of Hanoi to the world," Chung said. "And at the same time create new a playing ground and experiences for people of all walks of life."

Formula One has 21 races listed on a tentative calendar for 2019.

The 2018 season has two races to go, in Sao Paulo and Abu Dhabi.

Carey came into F1 intent on expansion and another event in Asia is a major part of the strategy.

"The energy of this country is incredible. The city of Hanoi I think is increasingly one that's capturing the world's imagination," he said. "Asia is clearly very important overall to our future.

"It's really the driving engine of the world's future, so as we look to grow this sport in Asia, we want to be in a country we really think it's going to be the engine of growth, the engine of excitement, so we think Vietnam really captures people's interests."

The race in Vietnam will join other stops in the Asia-Pacific region that include Japan, China, Singapore, and Australia. F1 had a regular stop in Malaysia from 1999-2017 and also had brief forays into India and South Korea.