Triple world touring car champion Andy Priaulx believes he is being deliberately blocked from successfully defending his title because organisers want someone new to take the honours.

BMW, Priaulx's team, have dominated the series for the past three seasons but this year rivals Seat have left everyone behind with their impressive TDI diesel-powered Leon cars, with fourth-placed Priaulx 15 points behind Seat's series-leader Gabriele Tarquini.

Priaulx believes Seat have such an advantage over the petrol-driven cars that organisers should introduce greater ballast penalties to slow them down, or revamp the rules to make the racing more equal.

Now, as he prepares his BMW for the Brands Hatch rounds of the World Touring Car Championship this weekend, Priaulx claims a determination to break his hold on the championship is behind a plot to make him uncompetitive.

He said: "Seat are operating within the regulations but whether those regulations are fair is another matter. They were there before turbo-diesel engines produced the kind of horsepower they are now. If BMW had brought out a turbo-diesel, how would everybody have reacted? Would they have slowed it down? I would say, yes.

"There is clearly a feeling among the other drivers and manufacturers that they want to see a new winner and the way it is going my championship will be lost in the next few races."

With his frustrations mounting there is growing speculation that the BMW works teams will quit the WTCC after this season.

Priaulx added: "I will be guided by BMW, who are not making any decisions at the moment. I have worked hard to get where I am and I don't like the feeling that someone is trying to steal my title."