Honda will quit Formula One on Friday, BBC Sport understands.
The Japanese company hopes to sell its team, which costs £200m a year to run, but is prepared to close the team early in 2009 if no buyer is found.
Sources told BBC Sport the team were "optimistic" they would continue, but an investor had yet been found.
According to the Reuters news agency, team bosses Ross Brawn and Nick Fry fear Honda could close the Brackley-based operation within weeks.
According to a Reuters source, Brawn and Fry told a meeting of the Formula One Teams' Association: "They have a month to find a buyer, otherwise they are closing the team."
Honda appointed Brawn, the man who masterminded seven world titles for Michael Schumacher, as their team principal prior to the start of the 2008 season.
Briton Jenson Button, who drives for the Honda team, will be left unattached for the 2009 season if the team folds, though some places with mid-ranking teams remain.
After recently cutting road vehicle production as a response to the global economic crisis, Honda is expected to make an announcement regarding the team's future early on Friday.
A notoriously expensive sport in which to compete, F1 teams have spent recent months in intensive discussions over cost-cutting measures.
I am told that for £1 you can now buy the Honda F1 team
Adam Parsons
BBC sports news correspondent
Max Mosley, president of world motorsport governing body the FIA, recently urged teams to find ways to reduce costs.
"Formula One is becoming unsustainable," said Mosley in July.
"The major manufacturers are currently employing up to 1,000 people to put two cars on the grid. This is clearly unacceptable at a time when all these companies are facing tough market conditions."
In October, a deal was reached to reduce costs for smaller teams in 2009 and 2010.
Considered a major player within Formula One, Honda bankrolls more than 800 staff at the team's Northamptonshire base and has the largest budget in the sport.
BBC Radio 5 Live's F1 commentator, David Croft, said Honda's withdrawal could have profound consequences for the sport.
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