Dozens of Nestl workers in York walked out today in a dramatic bust-up with their own union.

About 170 staff on the assortments production line marched out of the factory in the latest twist in the row over the chocolate-covered pretzel snack, Flipz.

The workers said they were furious that they were being denied extra hours, on which many rely, so that casuals on the now-halted Flipz line could have work.

They said they were being made to look "mean and greedy" for not wanting to give up the chance of extra hours.

In a split with their own union, the GMB, dozens of workers swamped the office of George Tutill, the chief shop steward today. They demanded a union apology over comments made in last night's Evening Press in which the GMB's Graham Waite said the work should be shared out.

Ruby Green, who works on the assortments line, said: "When Flipz started, the management took on casual staff on short-term contracts. Now Flipz has stopped they are giving the casuals the extra hours we would normally have. We are angry that we are being made to look mean and greedy. They could have done away with all this if they had offered the jobs on a temporary basis and then filled in anything extra with temps."

Mr Tutill said today more than 100 staff had walked out in the unofficial strike.

He said the employees, mostly women, were refusing to recognise union policy and had downed tools without GMB's backing.

He said: "They've all just walked out. Obviously the union is in a bit of a position, we try and support the workers but we must follow union policy.

"The union official is coming up this afternoon and our position may change, but at the moment this strike cannot have the support of the union."

Nestle spokesman Paul Kirkwood said today: "We are disappointed that people have felt the need to take this action. We cannot comment any further at this stage."

Yesterday it emerged that Nestle will lay off 51 casual workers - rather than the 90 announced last week - for a fortnight after talks with the GMB. But 80 will stay on absorbed into other departments at the factory, including assortments.

Chief shop steward George Tutill said today's strike was unofficial and he urged staff to return to work, but his pleas only met with jeers from the workers. He told the Evening Press: "I can only carry out trade union policy. We have never been in this position before."

Efforts to unlock the stalemate were taking place this afternoon when Mr Waite, the Yorkshire and North Derbyshire regional officer for the GMB arrived after he was phone by Mr Tutill.

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