Formula One will not have 20 races next year despite the sport's governing body FIA publishing a list with that number of dates on it, Bernie Ecclestone said on Friday.

"I blocked off 20 dates but we can change some around," the commercial supremo told BBC radio at the French Grand Prix.

"Eighteen, 19, 17 -- who knows," the Briton added when asked how many races there would be next season. "Not 20, I can assure you."

This year's championship is already the biggest in Formula One's 55-year history with 19 races, incorporating Turkey for the first time, and several team bosses have said that is too many.

The calendar is drawn up by Ecclestone but has to be approved by the FIA (International Automobile Federation).

Mexico has been expected to appear on the calendar next year with a new circuit yet to be built in the Caribbean resort of Cancun but Ecclestone appeared to cast doubt on that race happening.

"I don't know about Mexico, I haven't been there for a long time," he said.

Asked about the chances of Formula One returning to the United States, he replied: "I hope 100 (percent). That's what I'm working on."

This year's race seriously damaged the sport's image in America with just six cars competing at Indianapolis on July 19 after the seven Michelin-equipped teams withdrew on safety grounds following tyre failures in practice.

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