Following the demise of the Magny-Cours event, French authorities this month finally unveiled detailed plans for a new grand prix venue.

There is no guarantee France will return to the formula one calendar in 2011, Bernie Ecclestone has admitted.

Following the demise of the Magny-Cours event, French authorities this month finally unveiled detailed plans for a new grand prix venue.

A layout at Flins-Les-Mureaux, northeast of Paris, is slated to be targeting a 2011 debut, with construction to shortly begin.

But asked whether the project is the solution to the current absence of historic France from the calendar, F1's chief executive answered: "I don't know.

"There are still the protests of the nearby residents and the mayor," Ecclestone told the German news agency SID.

"However the prime minister supports the project, which is very important," he added.