Jean Todt says he will not respond to Bernie Ecclestone's recent comments about Formula E.

88-year-old Ecclestone was ousted by F1's new owners Liberty Media in 2017. He said recently that the category should be "concerned" about the growing popularity of the all-electric category Formula E.

"I do not react to such provocations," Todt, the president of the FIA, told Auto Bild.

Todt was speaking in Paris, on the sidelines of the French capital's Formula E race. The FIA sanctions both Formula E and F1.

"My dream was always to get formula one to Paris," said the Frenchman. "We have done that with Formula E."

But he said the two categories should not be compared.

"Formula one is no longer a baby. It is a 70-year-old adult. So we have to see that we translate what we have learned in formula one into other categories such as Formula E," said Todt.

"We want to prevent the sort of dominance we see in formula one, and also reduce the costs because we feel that formula one is too expensive," he added.

"But formula one is and remains the premier class of motor sport."

As for Ecclestone's comments, Todt dismissed them but said: "Of course we have to stay focused in formula one as we improve the racing.

"For me as FIA president, every series is important. I do not have favourites. They are different and I like them all."

But some say Formula E is clearly the series of the future, as it has exclusive rights to all-electric engines and the support of many carmakers.

Todt insisted: "Formula one also drives with state of the art power units. We have hybrid cars whose engines are already fascinating. They have about 50 per cent thermal efficiency.

"We should talk about that much more," he said.

Also rumoured at present is that F1 might be looking into using synthetic fuel in the future.

"We are always working on what might come next," said Todt. "We also need a vision for formula one."