CADBURY workers fear their jobs are on the line with the chocolate firm set to be bought by the same US rival that cut Terry’s historic ties with York.

One Cadbury employee said colleagues were very worried after the board of the Birmingham- based firm recommended shareholders accept a revised bid from Kraft Foods.

So great was the concern that the Prime Minister stepped in to offer reassurance to workers.

Unions have warned that jobs would be put at risk by the deal because Kraft would be weighed down by a debt of about £22bn. It is expected to borrow £7bn to finance the Cadbury deal.

Business Secretary Lord Mandelson and trade unions are now seeking urgent meetings with Kraft to gain assurances about jobs.

If Kraft’s £11.9bn recommended bid is accepted, it will end the independent history of the British firm dating back to 1824.

There are echoes of the Terry’s factory in York, which Kraft shut in 2004, despite the firm being founded in the city in 1823.

After restructuring, Kraft moved production to factories in Sweden, Belgium, Poland and Slovakia, 11 years after buying Terry’s in a £220m deal.

Last night, Kraft pledged ‘‘great respect for Cadbury’s brands, heritage and people’’, but its plans for “meaningful cost savings” raised fears that thousands of job losses could follow.

Cadbury employs about 45,000 people in 60 countries, with 5,600 staff at eight manufacturing sites in the UK and Ireland, including its Bournville factory in Birmingham, and a facility in Somerdale, near Bristol, which is scheduled to close.

One worker outside the Bournville plant said: “Nobody really knows what is going on or what this might mean in terms of job losses, but inside that factory there are a lot of people who are very, very worried about the future – the future of the company and their own future, their jobs and their families.”

John Flavin, Unite the union convenor at the Bournville plant, said he was very surprised that Kraft’s offer had been approved by the board but vowed to do everything possible to save jobs at the plant.

He said: “Our role is to continue our campaign to maintain this as an independent business and also to lobby the shareholders to show them the benefit in staying with Cadbury, as opposed to turning the business over to a debt-ridden company with something like £22bn that will have to be paid back at some point and will probably cost my members their jobs.”

Prime Minister Gordon Brown said: “We are determined that the levels of investment that take place in Cadbury in the UK are maintained and we are determined that, at a time when people are worried about their jobs, that jobs in Cadbury can be secure.”

If the takeover is successful, Kraft will become the world’s largest chocolate and sweets firm. It is presently second to Mars.

Cadbury bosses had previously described Kraft’s initial hostile approaches as derisory.

Cadbury chairman Roger Carr had previously led a robust defence of the firm’s independence and blasted Kraft’s “low-growth, conglomerate business” as an unattractive prospect.

Yesterday, Mr Carr said: “We believe the offer represents good value for Cadbury shareholders and are pleased with the commitment that Kraft Foods has made to our heritage, values and people throughout the world.”

Cadbury shareholders have until February 2 to accept Kraft’s revised bid.

Speculation still remains over a possible offer from US rival Hershey that could yet derail the Kraft deal.

Hershey, which makes Dairy Milk bars and Creme Eggs under licence in the US, was yesterday given a deadline of Monday by the City takeover watchdog for it to make an approach or walk away.

Timeline: Cadbury's fight against takeover

September 7 – Kraft makes its initial £10.2bn takeover approach, but says that Cadbury has already rejected its advances.

September 12 – Cadbury issues an open letter to Kraft chief executive Irene Rosenfeld criticising its bid. Chairman Roger Carr hits out at the “unappealing prospect” of the chocolate maker being absorbed into Kraft’s low-growth, conglomerate business model.

September 30 – A Takeover Panel ruling instructs Kraft to announce its intention to either make a firm offer or not to bid for Cadbury.

November 9 – Kraft announces a £9.8bn hostile takeover bid, which is promptly dismissed as derisory by its target.

November 18 – Confectioners Hershey and Ferrero join the fray, raising expectations of a bidding war for Cadbury, with statements saying they were considering their options over the firm.

November 23 – Cadbury’s shares hit a two-year high.

December 4 – Kraft officially launches its 60-day hostile takeover effort by posting details of its cash and shares offer to Cadbury shareholders.

January 5 – The US firm pledges to sweeten the cash part of its offer and said it was selling its North American frozen pizza business to Nestle for $3.7bn (£2.3 bn) in order to fund the revised proposal.

But Kraft suffers a setback when its biggest shareholder, Berkshire Hathaway, headed by billionaire investor Warren Buffett, voices concern over the takeover. Meanwhile, Nestle confirms it has no intention of making a counter bid.

January 12 – Cadbury urges shareholders not to let Kraft “steal your company” in a defence document that hailed outstanding trading last year and forecast up to seven per cent sales growth this year.

January 14 – Another bullish defence from Cadbury reveals good growth across its chocolate, sweets and gum divisions despite mixed trading conditions.

From the grocery store to global name

● Quaker John Cadbury opened a shop in Birmingham’s Bull Street in 1824, selling tea, coffee and hot chocolate – as an alternative to alcohol.

● He started manufacturing commercially in the 1830s and Cadbury Brothers was formed when his brother, Benjamin, joined in the 1840s.

● The brothers opened an office in London and received a Royal Warrant as manufacturers of chocolate and cocoa to Queen Victoria in 1854.

● In 1861, the mantle was passed to John’s sons, Richard and George.

● In 1879, a new “factory in the garden” was built on land outside Birmingham. The site was named Bournville and, from this, George created a visionary model village for industrial workers. By 1900 the estate included 330 acres of land with 313 cottages housing workers from Cadbury and elsewhere. The Bournville Trust still exists and the village is home to about 25,000 people.

● Cadbury launched its first solid milk chocolate for eating in 1897. A few years later, Dairy Milk was launched to rival Swiss milk chocolate brands, followed by Milk Tray.

● It merged with JS Fry & Sons in 1919 to compete against Rowntree. Cadbury joined Schweppes in the Sixties, but the firms split in 2008.

The company also bought out Trident and Stride in 2003.

● UK and Ireland is the largest section of Cadbury’s business, and revenues were £1.27bn in 2008.

● The firm has seen annual profits rise 30 per cent to £559m.