Formula 1 could still hold a world championship this year even if the season cannot start until October, managing director Ross Brawn says.
Brawn said F1 was looking at closed-door races as a way to start the season once the coronavirus crisis eases and "every permutation is being discussed".
F1 must run eight races for a season to be classed as a world championship.
"If you wanted a drop-dead point (deadline), it would be October," Brawn said.
"But then there's always the possibility we could run into next year, and that's being explored - could we stray into January to finish the season."
Brawn, talking to Sky, said there was no point starting the season unless it could be kept going and pointed out that races on permanent circuits were easier to re-schedule than those on temporary tracks such as street circuits.
The Monaco Grand Prix has already cancelled permanently this year, while the other eight races called off so far have only been postponed, with the hope of rescheduling them later on.
Brawn said he believed the 2020 season could include anywhere between eight and 19 races and that plans for how to approach a season were changing almost every day. "It's a very dynamic and volatile situation," he said.
An F1 spokesman said Brawn views October as the final possible starting date for a season that contains eight races and finishes before the end of the year.
To get 19 races into the schedule, the season would have to start in July with the likelihood of running into January 2021.
"We're looking at the logistics of a closed race, how we would get the people there, how we would protect them, how we would make it safe," Brawn said.
"We could have a very enclosed environment where the teams come in on charters (flights), we channel them into the circuit, we make sure everyone's tested, cleared, there's no risk to anyone and we have a race without spectators.
"That's not great but I think it's still better than no racing at all.
"I think we have to remember there's millions of people that follow the sport sat at home... to be able to put on a sport and entertain people would be a huge bonus with this crisis we have."