Apr.3 (GMM) The formula one calendar is set to expand to twenty grands prix as early as next year, team bosses suggested in Bahrain on Wednesday.

Abu Dhabi is preparing to host its inaugural race next year, and South Korea in 2010. The current calendar features 18 stops.

But with India, the United States, Russia, Dubai and Qatar possibly also clamouring for hosting rights, the team bosses warned that while F1 needs to embrace expansion, there should be limits.

"My firm belief is the season should expand to not more than twenty grands prix," McLaren boss Ron Dennis told delegates at the Motor Sport Business Forum Middle East at the Sakhir circuit.

"Twenty is about the right number," Honda CEO Nick Fry agreed, while Red Bull's Christian Horner added: "Twenty is a big number, but it's a sensible number".

"It's a huge logistical challenge but the way the teams are working with each other to self-regulate testing it is possible," he added.

Fry said it is obvious that the recent trend for new venues is in the Asian and Middle Eastern regions.

"F1 needs to go where the commercial market is", he said, albeit insisting that the "balance of traditional circuits within Europe and new countries and continents is vital".

Dennis is also happy with F1's expansion, but baulks at the concept that it should be at the expensive of the winter 'closed' season.

"The closed season is essential not only for logistical reasons but also in order to stir up a sense of anticipation in the hearts and minds of F1 fans," he said.