Toyota's F1 budget for 2010 has yet to be confirmed
Toyota's future in Formula 1 is not guaranteed after it emerged that their 2010 budget has not been agreed with the team's Japanese parent car company.
Toyota's F1 boss John Howett told Autosport that the budget had been submitted but they were not expecting a decision until later this year.
"I am honestly expecting severe pressure on budget," confirmed Howett.
Toyota have signed up to the Concorde Agreement which theoretically commits them to F1 until the end of 2012.
"We have submitted the budget and because of the economic situation, the Toyota group wants to wait for the full half year of the current financial year [before signing it off]," said Howett.
Toyota's Italian driver Jarno Trulli added to the uncertainty surrounding the team's future when he suggested another car manufacturer could leave the sport.
"In this economic crisis, nothing is sure," said Trulli, whose contract talks with Toyota for next year have yet to be finalised.
"If you look back over the last year it is a disaster. Honda has pulled out, BMW has pulled out, and probably they will not be the only ones.
"I think you can expect anything. Nothing is sure at the moment, because there are plenty of things which have happened, and from one day to another the situation changes."
Toyota has previously scaled back its Formula 1 operations by passing up on its right to host the 2010 Japanese Grand Prix at the Fuji track which the company owns.
Instead the 2010 and 2011 races - along with this year's event - will be held at the Honda-owned Suzuka circuit
Concerns over Toyota's future in the sport come against the backdrop of fellow car manufacturers BMW and Honda pulling out of Formula 1.
BMW announced in July that they would quit F1 at the end of this season, the German car giants citing "current developments in motorsport".
Honda pulled out of Formula 1 in December 2008, the team blaming the world recession for the decision.