F1's all-new era risks "destroying" the sport, according to outspoken 1997 world champion Jacques Villeneuve.
The French-Canadian, often referred to as an F1 'purist', admitted he is no fan of the radical new rules, featuring energy recovery-bolstered V6 engines.
"I think personally the rules are too restrictive; it's not formula one," he told the Telegraph.
42-year-old Villeneuve, whilst announcing his participation in the FIA world rallycross championship this year, said the rules are even a step back from 2013, when drivers often nursed fragile Pirelli tyres to the flag.
Now, the major challenge will be getting a limited amount of fuel to the finish, but the former Williams and Sauber driver said: "It's not even the driver who determines how much fuel he's saving -- it's all done electronically.
"I don't see the point. I know it's the concept of trying to make it look 'greener' because people will be happier, but ultimately it's not greener.
"It's not F1. It's just a perception, that is destroying formula one a little bit."
Villeneuve also said the recent Jerez test showed that the new technology is too complex, while the cars are too slow.
"The laptimes (at Jerez) were barely faster than what we did in 1997 in Jerez ... that's 17 years ago. I'm not sure why it has become so important to keep going slower," he said.
Villeneuve was also scathing of the unpopular 'double points' innovation for 2014, designed to keep spice in the title fight until the very end.
"It's turning F1 into a non-epic show, or a game, instead of a proper sport," he said. "In a way it's saying, 'We're losing fans, how can we make it fakely more exciting?'"
Amid all the speculation about F1's new era, however, Ferrari team boss Stefano Domenicali thinks it is too early to draw any dramatic conclusions.
The Italian insisted "a propensity for self-destruction serves no purpose".
"We have only had one test so far when there were never more than four or five cars on track at the same time. Let's wait until we see all 22 together before saying that everything's gone wrong," said Domenicali.
"Once a path has been chosen, one has to move forward in a constructive manner," he added.