Formula 1 boss Bernie Ecclestone has revealed Marussia and Caterham F1 will not take part in next weekend’s US GP at Austin.

The Caterham squad has already been granted special dispensation to miss the next two races on the calendar while administrators search for a new buyer, having taken control of the squad earlier this week.

It has also been well documented that fellow F1 minnows Marussia have also been struggling financially. The team fielded just one car for the Russian Grand Prix for Max Chilton, while team-mate Jules Bianchi remains in hospital having incurred a serious head injury following a crash at the Japanese Grand Prix.

“Neither of those two teams are going to go to America,” Ecclestone told Reuters.

If Caterham F1 and Marussia fail to compete in Austin, F1 with encounter its lowest grid since the 2005 Monaco Grand Prix. Back-to-back races in America and Brazil could mean that Marussia will miss the penultimate round of the season at Sao Paulo with cars due to be transported directly from the Circuit of the Americas to Interlagos.