Red Bull team principal Christian Horner said Formula One has become too predictable and believes dramatic rule changes are needed to bring teams closer together.

Mercedes have taken out the past two constructors' championships, finishing over 270 points ahead of their nearest rivals on both occasions.

Horner is adamant big changes need to be made to the sport, or people would tune out.

"Predictable, serial results and serial winning is difficult for any sport," Horner told Autosport.

"We were accused of it, but we enjoyed the continued success and longevity of the sport. Two of our world championships went to the last race, and we never finished first and second in a championship.

"Inevitably, with predictability, people get turned off and it needs a rejig to bring it closer together. I don't think anyone wants to see Fernando Alonso just taking part, we want to see him competing.

"We want to see Daniel Ricciardo competing, and we want to see Sebastian Vettel competing against Lewis Hamilton and Nico Rosberg.

"You can't expect the teams to achieve that, that's for the regulator and the governing body to come up with a set of rules that achieve those objectives."

He added: "It is vitally important, so we need strong leadership from the commercial rights holders and the governing body to plot a path for the future that addresses what the fans need and what the fans want to see.

"Without them, there is no Formula One [and it] ultimately has to be a show, has to be entertainment, and it has to appeal to a broad spectrum of fans and spectators.

"The regulations are incredibly stable for next year, so Mercedes will inevitably carry on the dominance, such is their margin."