Formula One's season was thrown into turmoil on Friday with the Australian Grand Prix cancelled just hours before cars were due to hit the track, and races in Vietnam and Bahrain subsequently called off as well as the coronavirus pandemic takes its toll.
The decisions follow the postponement last month of April's Chinese Grand Prix, leaving motorsport chiefs scrambling to revise the calendar and proposing the end of May as a potential start date for the season.
"The global situation regarding Covid-19 is fluid and very difficult to predict and it's right we take time to assess the situation and make the right decisions," F1 chief Chase Carey said in a statement.
"We are taking this decision with the FIA and our promoters to ensure the safety of everyone involved in Formula 1 and our fans."
Formula One and the FIA, world motorsport's governing body, said they "expect to begin the Championship in Europe at the end of May but given the sharp increase in Covid-19 cases in Europe in recent days, this will be regularly reviewed."
The Dutch Grand Prix is the next race on calendar, although its scheduled 3 May date will be pushed back. The Spanish Grand Prix in Barcelona was planned for the following week.
The future of the Australian race, the first of the season, was in doubt Thursday when McLaren pulled out after one of its team members tested positive for the virus.
McLaren revealed Friday that 14 other staff were now in a mandatory two-week quarantine after being in close contact with the man.
The McLaren employee was among eight Formula One personnel who went into isolation after showing flu-like symptoms typical of the disease this week.
The other seven - including four from the Haas team - all returned negative results.
The fast-moving developments sparked a crisis meeting between the race organisers, the FIA, teams and Formula One promoters late Thursday to discuss whether Sunday's race should go ahead.
"Those discussions concluded with a majority view of the teams that the race should not go ahead," they said in a joint statement just hours before the first official practice session and with fans queueing to get in.
Teams quickly began packing up to leave the circuit as some fans, many travelling from overseas, fumed at the way they were treated.
"We had to find out from Twitter, not from the organisers and have been waiting here for hours in the line," one told the Herald Sun newspaper.
Hours later, Vietnam postponed its debut F1 Grand Prix as the race became the latest to fall victim to a virus that has killed over 5,000 people, with cases around the world topping 134,000, according to an AFP tally.
Scheduled for 5 April, the Grand Prix in Hanoi was set to be the third race of the season and the first-ever to be held by the communist country.
Last year Vietnam signed a 10-year deal with Formula One to host an event state media said would cost the country $60 million per year.
The Bahrain race planned for 22 March was due to be held behind closed doors, but it too was shelved.
Bahrain has shut schools and axed some flights in order to curb the spread of the virus. It has also asked visitors from high-risk countries to self-quarantine for a fortnight.
"Formula 1 and the FIA continue to work closely with the race promoters in Bahrain and Vietnam and the local health authorities to monitor the situation and take the appropriate amount of time to study the viability of potential alternative dates for each Grand Prix later in the year should the situation improve," the statement added.