BERLIN (AFP) - Mercedes' world championship stranglehold has made Formula One 'boring' and caused spectators to turn their backs on the sport, commercial ringmaster Bernie Ecclestone told Welt am Sonntag on Sunday.

"The domination of Mercedes is so strong that a good number of people watch the start of a race and then switch off their televisions because Mercedes have made races boring," said Ecclestone.

"It is not good for the sport. Fans don't want to know before the start of a Grand Prix who is going to win. It's a problem for us at the moment and one that we must resolve."

Mercedes have swept to the last two F1 world titles with Lewis Hamilton taking back-to-back drivers' crowns.

That dominance has forced Ecclestone, the powerful head of Formula One Management (FOM), to admit he is worried for the sport's future.

Ecclestone believes that teams and manufacturers need to co-operate more to make the sport more affordable and attractive and agree on a package of reform measures.

"For decades, we have tried to limit financial operations to guarantee more competitiveness," added Ecclestone who believes more powerful and cheaper engines are key to achieving a level playing field.

This season, Hamilton and Mercedes teammate Nico Rosberg, who was second in the championship, shared 16 wins in 19 Grand Prix and finished one-two on 12 occasions.