The BBC said the move followed the arrest in August of Hanoi People’s Committee chairman Nguyen Duc Chung. A source with knowledge of next year’s calendar confirmed to Reuters that the race was not listed.
Formula One said the draft schedule would be issued on Tuesday.
The calendar will still have to be approved by the governing FIA’s World Motor Sport Council, usually a formality.
One confirmed new destination is Saudi Arabia, due to host a race for the first time in Jeddah in November.
The calendar could still stretch to a record 23 rounds, despite the absence of Vietnam, with the return of some of the circuits used this year to patch gaps left by cancellations due to the pandemic.
Portugal’s Algarve circuit, Imola in Italy and Turkey’s Istanbul track would be the leading contenders to take Vietnam’s April 25 slot.
Brazil is also set to remain on the calendar, despite earlier doubts, with South America’s only race returning to Sao Paulo’s Interlagos circuit in November rather than one yet to be built in Rio de Janeiro.
The Rio circuit is controversial for environmental reasons and work has yet to start on it.
The calendar will otherwise see the return of races cancelled this year, including the Dutch circuit of Zandvoort which last hosted a race in 1985 and would follow on from Belgium’s Spa in September.
The season is set to start with the Australian Grand Prix in Melbourne on March 21.
Formula One is hoping to allow fans back at circuits after racing this year behind closed doors or with very limited attendance.