The Vietnamese Grand Prix will not feature on the 2021 Formula 1 calendar after being dropped at the last minute.

An initial schedule comprising 22 races is set to be published by F1 on Tuesday, though the calendar could rise to 23 events if a replacement for Vietnam is found.

Vietnam had been set to stage its first-ever grand prix around the streets of Hanoi in 2020 prior to its cancelation due to the coronavirus pandemic. The race was initially postponed until 2021, but it has been dropped altogether at the 11th hour.

BBC Sport has reported that the move to axe Vietnam from the schedule was triggered by the recent arrest of Hanoi People’s Committee chairman Nguyen Duc Chung, who was a key figure in the running of the race.

Brazil’s Interlagos circuit is set to remain as the host of the Brazilian Grand Prix for 2021 with work on a planned new track in the Deodoro area of Rio De Janeiro still awaiting the green light from the government.

An F1 spokesperson said: "Our calendar will be announced tomorrow [Tuesday] and we are not going to give a running commentary before its publication.

"It also needs to go to the World Motor Sport Council for approval.”

The Australian Grand Prix in Melbourne is set to retain its traditional March slot as the opening round of the 2021 campaign, while the inaugural Saudi Arabian Grand Prix has already been confirmed as taking place on 28 November as a night race around the streets of Jeddah.

F1 CEO Chase Carey has stressed the championship is currently working on finalising a calendar that will look “closer to normal” after the opening 10 rounds of the original 2020 schedule were called off due to the coronavirus pandemic.