Former Formula 1 world champion Sir Jackie Stewart does not think the British Grand Prix is in doubt despite the decision of the man in charge of the race to resign.

Stewart is also confident the Silverstone race has a future despite negative comments made by F1 supremo Bernie Ecclestone.

Rob Bain, the chief executive of Silverstone leaseholders Octagon Motorsports, resigned on Monday.

Stewart believes the work done on improving roads around the circuit and also to the entrance and exit will help ensure the future of Britain's top motorsport event.

"We have made such big steps forward," said Stewart. "The masterplan for Silverstone to create a centre of excellence is on course," he told Radio 5 Live.