A slump in the demand for crisps has been blamed for the closure.

Bosses said meetings with union leaders and other parties had begun "with the intention of seeking ways to mitigate the impact of the closure on all staff".

Talks between management and trade unions failed to save the plant at Widnes, Cheshire.

In a statement, the company said: "Over the past few weeks the company has had extensive discussions with the trade unions, Halton Council, Derek Twigg MP and the Department of Trade and Industry.

"All parties have been striving to come up with options to keep the site open.

"Each suggestion has been fully investigated by the company. Regrettably none has proved to be viable."

Clive Rimmer, of the Transport and General Workers Union, said he believed the closure was a "fait accompli".

"Even if everyone had taken a 20% pay cut and changed terms and conditions we would still have been millions short of saving the �11m they wanted," he said.