Whilst revealing this week that 40,000 tickets have been sold so far for the forthcoming August 29 event, the officials said Spa is under increasing pressure from international venues who have more money to spend.

"The ticket sales for this year are relatively good," said spokesman Christian Lahaye.

"We hope to reach the figure of 2007, with 65,000 tickets sold, to allow us to achieve a balanced financial position," he added.

According to the Flemish newspaper De Morgen, Spa's F1 future could depend on the new Concorde Agreement post-2012 expanding the annual calendar to up to 25 races.

With the influx of new international races promising much higher annual promotion fees, the report said Spa-Francorchamps' race organizers are worried.

"There is no shortage of candidates (for grands prix)," Spa-Francorchamps circuit boss Andre Maes is quoted by Belga news agency.

"Even France doesn't have a grand prix," he said.