Germany and Italy could lose races

Germany currently has races at the Nurburgring and Hockenheim but Ecclestone, who draws up the calendar, told Reuters at the French Grand Prix that could be trimmed to just one round.

"We're working on it, probably only one," he said. The same applied to Italy, which has the historic Monza circuit and Ferrari's home track at Imola.

"It looks like it," said the Briton.

Neither German circuit is making the money it used to and Hockenheim track operators said last December that they were considering holding races in alternate years.

This year's calendar has 18 rounds, after a record 19 in 2005, because Spa was cancelled in February after the local promoter went bankrupt.

Ecclestone said Spa, where seven-time champion Michael Schumacher took his first Grand Prix win in 1992, was expected to return.

Japan could also get a second round, with the Toyota-owned Fuji circuit confirmed as the new Japanese Grand Prix venue towards the end of next year but Honda's Suzuka hoping to be retained as a Pacific race.

Mexico, which last hosted a Grand Prix in Mexico City in 1992, and South Korea have also been mentioned as future Formula One hosts but Ecclestone said both countries were still "way down the road".

Formula One has no new races this season after welcoming Turkey's Istanbul Park circuit in 2005 and state-of-the-art tracks in China and Bahrain the previous year.