Bernie Ecclestone has cast doubt on the Grand Prix of America, which was due to take place in 2013.

According to the President of Formula One Management, organisers have missed deadlines, which has thrown the entire concept into doubt.

Ecclestone said: "We are waiting for different parts of the contract to be agreed. They are late.

"I don't know if it is going to happen. They are sorting things out internally with some of their funds. If they are ready for 2013 we will have them."

The race was due to take place on public roads alongside the Hudson river.