Cyril Abiteboul thinks F1 should think seriously about slashing the weight of the cars.

The Renault boss says it is an alarming development that, year on year, the cars get heavier and heavier.

"Next year it will be 850 kilograms in the race," he told Auto Motor und Sport.

"Even in Singapore the cars were so slow in the race that they were not a challenge to drive."

Indeed, the cars' weight is going up for 2019 due to the addition of a minimum driver weight and extra fuel for the race.

Abiteboul said: "We spend so much money making the car lighter, and yet the cars keep getting heavier.

"When the drivers are slow in the race then they no longer make mistakes, making it boring for the audience.

"In the 90s and 2000s, the drivers were really struggling with much lighter cars.

"We have to be careful," the Frenchman warned. "Interest in formula one is going down. The sponsorship market is difficult."

And he denied that the 2019 technical rule changes will at least make the racing more exciting.

"Honestly, after our work in the simulator and the wind tunnel, we do not believe it will become easier to overtake," said Abiteboul.