Sky News understands that Vauxhall job losses and plant closures are "almost inconceivable" as the race to buy General Motors Europe gathers pace.
Concerns have grown for the future of the Vauxhall brand as General Motors looks to offload its European operations.
Vauxhall employs more than 5,000 people at Luton, Ellesmere Port and at dealerships across the UK.
Sources close to sale talks told Sky it was highly unlikely that the Vauxhall brand would be lost whoever bought GM's European operations.
Fiat confirmed this week it was looking at buying up Opel, GM's European operation.
The Fiat chief executive and Germany's economy minister met on Monday to discuss the move.
Karl-Theodor zu Guttenberg also said Fiat had pledged to keep the three main German factories if its bid went ahead.
The deal to absorb Opel comes as Fiat prepares to acquire the troubled US carmaker Chrysler.
Fiat said the double deal could create a mega motoring empire, raking in £70bn a year in revenue.
But union bosses in the UKare fearful of British job losses.
Tony Woodley, joint general secretary of the Unite union, said the move sent "shivers down my spine".
"Fiat has struggled for years to get back into profit and now they want to swallow two elephants - GM Europe and Chrysler simultaneously," he said.
"Inevitably, plants will be reduced across the EU if this takeover goes ahead, and there are real questions over what this will mean for UK plants where Fiat already owns similar operations."