Bernie Ecclestone has revealed that Formula One's teams have signed contracts agreeing to help competitors which get into financial trouble by supplying a car to them. It is a particularly pressing problem.

Sportsmail can reveal that the Marussia team notified London's High Court earlier this month that it intends to go into administration. It follows the collapse this week of F1's worst-performer Caterham.

Eleventh hour talks are underway to save it and Ecclestone says another team may have to step in by supplying it with a car. The controversial rule is written into the teams' contracts with Ecclestone and it forces them to field a third car if the grid slips below a threshold of 20 cars.

Caterham have gone in to administration as the team searches for a new owner

A security guard takes down a flag after the closure of Caterham's factory in Oxfordshire

It was thought that the teams would run the third car themselves but in fact it would be supplied to ailing rivals to stop them from going under.

'They would supply a third car to someone else so if, for example, Sauber disappeared, a team could do a deal with Sauber. Ferrari could say, ''we will give you a car, all that goes with it, and we want you to put this sponsor on it. You have your own sponsors but we want you to include this one as well and we want you to take this driver''. The team wouldn't have to go under then would they? If Red Bull decided they would give a car to Caterham for example that could solve their problem.'

The reason for the clause is that Ecclestone's contracts with race organisers state that F1 'shall use its reasonable endeavours to ensure...that at least sixteen cars participate in the Event.'

F1 supremo Bernie Ecclestone has revealed teams have contracts to supply ailing rivals with third cars

If it slips below that F1 could breach its contracts and risk losing the £300 million in fees paid by race organisers. Setting the threshold at 20 cars gives Ecclestone a buffer and he may need it. Annual F1 team budgets are now around £140 million on average and although Red Bull has one of the biggest, smaller outfits are struggling to keep up.

On 7 October Manor Grand Prix Racing, the company which runs Marussia, filed a notice with the High Court saying that it intends to appoint an administrator. The team lies in ninth place with just two points and has made combined net losses of £140.6 million since joining F1 in 2010.

Ecclestone said on Saturday that he expects Marussia and Caterham will miss next weekend's United States Grand Prix. It will put the grid at 18 cars but Ecclestone added that this won't trigger the third car clause because the teams' F1 contracts allow them to miss two races each year.

'We don't have to introduce a third car at this stage because they can miss a couple of races. They lose any money they would have got for those races but they don't lose their position in the championship. I have no idea if Marussia are going to make it in the long run. It's better if they didn't have to go into administration.'

Marussia has filed a notice with the High Court saying that it intends to appoint an administrator

Marussia have struggled to recover from the horror crash that left Jules Bianchi seriously injured in Japan

It is too late to prevent that happening to Caterham. Earlier this month bailiffs seized equipment from its factory in Oxfordshire and the team's 220 staff have been locked out of the building by the administrator since Thursday.

It languishes in 11th place, one behind Sauber which has failed to score any points this year despite having backing from sponsors owned by the world's richest man, Mexican tycoon Carlos Slim.

If a team received a rival's car it would not need to spend money on research and development, manufacturing or buying engines. These are the three biggest costs for F1 teams, far exceeding spending on staff and drivers which would continue to be covered by the outfit which receives the third car.

Lewis Hamilton will renew his rivalry with Nico Rosberg at the US Grand Prix, where both Caterham and Marussia have been granted special dispensation not to race

Marussia's latest company accounts are for 2012 and show that it spent £32 million on research and development which alone comes to 42% of its total £76.1 million costs. Manufacturing and engine expenses are estimated at a further £23 million. Wiping out these costs would transform bankrupt outfits into profitable ones which could attract investment and ultimately stand on their own two feet.

Some teams raced with three cars in the 1970s though this was because there was freedom to do so not because the grid had hit a threshold stipulated in contracts. Although the teams have signed up to supply third cars now, several of them, including Britain's Williams, have long opposed a similar scheme where outfits would sell customer cars to rivals.