China and USA set for two GPs as Liberty chases 25-race calendar

China and the United States are likely to be awarded a second grand prix each year as Liberty Media pursues a Formula 1 schedule including 25 races. F1's commercial director Sean Bratches also confirmed that a street race in Vietnam remains in the pipeline, although it is unlikely to feature in 2019.

F1 has visited China each year since 2004, while last year's United States Grand Prix was the 47th time the event had been held as part of the World Championship.

The Circuit of the Americas in Austin, Texas has hosted F1 since 2012, although the series has also visited famous American venues such as Watkins Glen and Indianapolis.

With over 1.6billion potential visitors across the two vast countries, however, Liberty is keen to visit both more regularly as part of an expanded calendar which would make an already packed schedule even more crowded.

"We see the United States and China as countries that could support two races," Bratches said.

"With the right economics, with the right structure and cadence of events across territories, 24 or 25 [races] is probably where we'd like to be from a longer-term standpoint.

"There's more interest than we have capacity in the schedule. We want to be very selective.

"It's very important for us as we move forward to go to locations that are a credit to the Formula 1 brand."

Former F1 supremo Bernie Ecclestone revealed that he had put a deal in place to take the sport to Vietnam shortly before handing the reins over to Liberty.

A Hanoi street circuit remains in place to host an F1 event in the future as Liberty looks to continue the sport's reach in Asia.

"We think Hanoi could come on in the next couple of years, and we're working with the Hanoi government to that end," said Bratches.

"This is a street race where we can go downtown, where we can activate a large fan base, and you have extraordinary iconography from a television standpoint."