McLaren boss Zak Brown fears up to four teams could drop out of Formula 1 during the coronavirus crisis and feels the sport must overhaul its financial practices and future plans to avoid “potentially devastating” situations.

McLaren became the first British-based team to furlough staff during the delays to the 2020 F1 season, with CEO Brown, other senior management figures plus drivers Carlos Sainz and Lando Norris all taking pay cuts to ease the financial pressure on the team.

While F1 has already postponed the technical rules overhaul by one year to 2022, but retaining the planned cost cap for next year, Brown has urged F1 chiefs to make further safeguarding measures to protect all teams as he fears almost half the grid could be forced out of the sport.

“Could I see - through what is going on right now in the world if we don’t tackle this situation head on very aggressively - two teams disappearing? Yes,” Brown told BBC Sport.

“In fact, I could see four teams disappearing if this isn’t handled the right way.

“This is potentially devastating to teams, and if [it is devastating] to enough teams - which doesn’t have to mean more than two - then very threatening to F1 as a whole.

“So I think F1 is in a very fragile state at the moment.”

Brown’s leading argument to help F1 is to reduce the cost cap further, which has been set at $150 million per season from 2021, down to as a low as $100m, but retain the same exemptions which includes driver salaries. That way teams can reduce costs while the sport still encourages a competitive F1 field by stopping bigger teams simply outspending rivals.

“You have everyone at $150m, and the strong majority - including one of the big teams - willing to come substantially under $150m,” he said.

"If we don’t make an aggressive enough budget cap and some people feel they have to top up this year and have no chance of getting it back, then they ask themselves: Why are they in it?

“I don’t think anyone competes in F1 just to make up the numbers.”

The McLaren boss also conceded putting staff on furlough due to postponements on the 2020 F1 season can as a tricky call but ultimately utilised to help financially protect the team.

“While we’re a well-funded racing team everyone has their limits - and as it relates to F1, it is no secret we lose a lot of money and my shareholders want value creation out of F1. So just letting the losses widen is not an option.

“I think there is a real danger in F1 that we as an industry can put our head in the sand on topics and now is not the time to put your head in the sand.”

Elsewhere, former McLaren chief Ron Dennis has also stepped up during the coronavirus pandemic through his foundation to deliver one million meals to NHS workers over three months.

“We built together in ten days one of the biggest infrastructures with some very unique abilities,” Dennis told ITV’s Good Morning Britain. “Working with the hospital we can identify those members of the national health who are physically ill and we will be delivering to their door through Yodel a five-day food pack.

“Thy cannot move between normal hospital rooms, they can’t go to the restaurant, so we are taking the restaurant to them.”