Formula One supremo Bernie Ecclestone has told US Grand Prix organisers that he could take the race elsewhere if he cannot agree a new deal with Indianapolis.

"It is not vital to Formula One to be in the United States," the 76-year-old told Britain's Daily Express newspaper on Thursday, three days ahead of this season's US Grand Prix.

"There are bigger markets for us to be in other parts of the world. We could be in India soon instead of the United States. We don't have a lot of sponsors from the US, no American teams and only one driver," he added.

"I get along with [Indianapolis Motor Speedway owner] Tony George and I hope we can strike a deal, but we have offers from other places in the U.S. too."

Indianapolis is in the last year of a contract for the Formula One race it has hosted since 2000. Ecclestone has talked in the past of taking Formula One to street circuits in Las Vegas [Images] or New York.

However, he also faces a squeeze on the calendar, with Valencia and Singapore confirmed as new races for next year while Abu Dhabi is due to make its debut in 2009 and South Korea in 2010.

India is also lobbying hard for a race and Suzuka is looking to return to the championship as a second Japanese race after being replaced by Fuji.

Despite Ecclestone's comments, similar to ones he made last year before agreeing a one-year extension with Indianapolis, the United States is a key market for the car manufacturers who dominate the sport and own most of the teams.

"The automobile market in the USA is the biggest one for Mercedes-Benz outside Germany [Images]," said Mercedes motorsport vice-president Norbert Haug, whose company owns 40 percent of championship leaders McLaren.

"For the BMW Group, the USA Grand Prix is of key importance in so far as the United States is our biggest market," said BMW Sauber boss Mario Theissen in a team preview of Sunday's race.

"We sell more cars there than in Germany and also have our biggest production sites outside Germany."

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