Manor GP enter as Virgin Racing
The International Automobile Federation published the official entry list with 12 confirmed teams and lingering uncertainty over the entry previously held by Toyota.
"Toyota Motorsport GmbH remains formally bound by the Concorde Agreement to put forward a team for participation, though it has indicated that it will not be in a position to do so," the FIA said in a footnote.
"An announcement will be made regarding this entry in due course."
The former BMW-Sauber team, now handed back to founder Peter Sauber following the departure of BMW at the end of the 2009 season, are likely to take Toyota's place having been assured already that they are the official reserves.
"Regarding the slot on the grid I am very confident that we will be given a final confirmation very shortly," Sauber, whose team plan to use Ferrari engines, told the official Formula 1 website.
"Our 2010 car is perfectly on schedule. The development and fabrication have been unaffected by the situation," he added.
"Having been able to proceed with uninterrupted development was also possible thanks to excellent cooperation with Ferrari, who submitted all the relevant data very early. Regarding the performance of the C29 we are all very confident."
Richard Branson's Virgin Group sponsored championship-winning Brawn GP, who have since been taken over by Mercedes, this season.
Virgin have yet to formally confirm their involvement with British-based Manor, one of four new teams due to make their debuts on the starting grid. Manor have signed German driver Timo Glock.
The other newcomers are US F1, Campos Meta 1 and Malaysian-backed Lotus F1 Racing.
Red Bull, championship runners-up this year, confirmed they will continue with Renault engines after considering other options.
Britain's world champion Jenson Button will have the number one on his car at McLaren with new team mate, compatriot and 2008 champion Lewis Hamilton competing as number two. Button won the title with Brawn.
Reuters