Bradford's biggest wool mill has called in the receivers - with more than 600 jobs under threat.

Historic firm W&J Whitehead is one of only two remaining wool-combers in the UK, but the Laisterdyke-based company says it has made the "reluctant" decision to appoint receivers because of "several months of reduced trading activity."

The topmakers and worsted spinning business, which was set up by two brothers in 1858, is blaming the strong pound, the US manufacturing recession, and increasing imports for the move.

In recent years the company has launched several initiatives to try to overcome the problems plaguing the UK textile industry, including investing in expensive, state-of-the-art machinery.

Last year it merged with fellow local firms Woolcombers and Daniel Illingworth, in a bid to make better use of its manufacturing capacity at Laisterdyke.

But a statement issued by W&J Whitehead confirmed that those efforts had not been enough.

It said: "A detailed review of our future trading position has indicated that there will be no recovery in demand in the short term.

"Therefore in the best interests of employees, customers and creditors, the board has had no option but to appoint administrative receivers."

Nick Halton, regional industrial organiser for the Transport and General Workers Union, said the news came as no surprise.

He said in February the company was extremely busy but the order book 'vanished' overnight because of the recession in America, where the company's core customers were based.

Since March staff have been on short-time, he said. "I have always had my doubts that the firm would still be trading by Christmas and, to be honest, there's no future for mills like this in this country anymore."

"It's advertised today but, despite the forecast improving in America, I doubt it will be bought, at least not to carry on as a textile mill - nobody is buying textile companies these days."

He said the company was a 'big animal' to feed and took a decision last week not to take any more orders because it couldn't afford the raw materials.

"Staff are very concerned, and obviously I will be doing all I can to save their jobs, but it looks doubtful.

"They have been promised redundancy pay but they are due to break up for their two-week holidays on Friday and are wondering if they'll get holiday pay."

No-one from the firm would comment further, but an employee at the mill, who wished to remain anonymous, said the workforce was in shock.

"There are more than 500 workers here, and a lot of us are up in arms about this," he said.

"Last week they told us we wouldn't be made redundant but now they're talking about going into receivership."

W&J Whitehead was Bradford's biggest remaining wool textile mill, and one of the UK's only two remaining wool combers - producing the 'tops' used for finer quality wool products.

Director general of the Bradford based Confederation of British Woolmakers, Paul Lambert, said its troubles marked the end of an era.

"Whitehead's was the biggest single site wool textile company in Bradford by quite a long way," he said.

"There used to be dozens and dozens of wool combing units in the city alone, so the fact we are now down to just one in the whole country represents a dramatic decline."

The strength of sterling over the last four or five years, which encouraged large retailers to look overseas, had caused the main problems for local businesses, he added.

In the industry's heyday, in the 1950s and early 1960s, it employed more than 200,000 people, mostly in Yorkshire - now that figure has shrunk to 15,000.

SMC Textiles in Birksland Street, Bowling, is now the only wool combing company in Britain of any size.

Director Brian Whitaker said: "It's a sad reflection of the state of trade, but it will benefit us in the short term, because we had been fighting over a shrinking market share."

*Peter Dunn and Simon Thomas, of Tenon Recovery, have been appointed as administrative receivers for the firm.