Gordon Brown has issued a blunt warning to any potential buyer of Cadbury not to move jobs out of Britain.
He said the firm’s success and its historic reputation depended on its British workforce.
The Birmingham-based chocolate-maker is continuing to fight off a hostile bid from US food giant Kraft, and is due to issue a document urging shareholders to reject the offier.
Chief Executive Todd Stitzer has indicated he would prefer to accept a rival bid from US confectioner Hershey if a sale is inevitable.
But union Unite has warned that it fears jobs will be lost if the firm goes into foreign ownership.
Cadbury employs 5,000 people in the UK, including at its famous headquarters in Bournville, Birmingham.
Speaking as he visited Birmingham today, Mr Brown said Cadbury had a big future - as long as retained its British links.
He said: “I think the important thing is that the good name of Cadbury is still capable of winning large business around the world.
“And that good name arises from the excellent productive capacity of Cadbury here in Britain.
“So I believe that the true value for Cadbury will mean that whatever its status, its going to still have a very big presence in our country.”
Earlier this week, Business Secretary Lord Mandelson promised the Government would speak out to defend British jobs if Cadbury was sold.
But he also stated that Ministers could not prevent a sale.
* Tomorrow's Birmingham Mail will have more on the Prime Minister's visit to the city.