Formula One will continue to be viewed as a minority sport by Americans even though the United States is due to host two grands prix a year from 2013, supremo Bernie Ecclestone said on Friday.
The United States, absent from the Formula One calendar since Indianapolis in 2007, returns to the schedule next year with a new race at Austin, Texas.
The country will then have two races a season from 2013 when a grand prix is also planned for New Jersey, on a street circuit against a backdrop of New York's Manhattan skyline.
Asked by television interviewer David Frost, in a programme to be aired on Al Jazeera on Friday, if he expected Formula One to be big in America in 10 years' time, Ecclestone said: "No.
"We've got a maximum of two races in America and when you consider the country is as big as Europe and we've got several races in Europe, it's difficult (for the United States).
"If we had a lot more races there and a lot more television it would be okay. It's (also) a bit like the rest of America in that they want to see a profit before they start something and it's not easy to do that."
The Briton said he was disappointed Turkey was missing from the 20-race calendar in 2012 and hinted strongly that South Africa would host a grand prix in 2013.
"I was talking to someone this morning about Turkey," said the 81-year-old.
"It is a pity we have lost that because I think it is one of those countries that's going to really move on in the world and that's why I went there in the first place."
Ecclestone said there were plenty of potential new grand prix hosts around the world but added he was loathe to extend the calendar beyond 20 races.
"We have enough countries waiting (to come on board) but I think we have to stop now," he said.
"It's difficult for the people who work in Formula One with all the travelling. They never see their families, that's the big problem."
Ecclestone said he was particularly proud about the improvements in driver safety during his 30-plus years in charge of the sport.
"If somebody has an accident today in a Formula One car, pick whatever speed you like, you see these guys have a big accident, undo their safety belts and get out - which is wonderful."