Marks & Spencer has hit back with a scathing attack on the GMB union in the row over the sacking of its “whistle-blower” employee.

The GMB said it was considering balloting its members at M&S to strike in what it described as “a campaign against what we think is corporate bullying”. The union represents the employee who was sacked by the retailer after he leaked changes in the company’s redundancy terms to the press.

In a statement, M&S said: “We are astonished by the actions and allegations the GMB has made about the dismissal of one of our employees. Despite claims that it plans to appeal on behalf of the individual, the GMB seems more concerned about conducting the case through the media to gain publicity for its own ends.”

M&S also outlined the reasons behind its decision to dismiss the employee who leaked the information to the press.

“The individual deliberately leaked internal company information about the review of our redundancy terms and made derogatory and speculative comments to the media about other subject matters,” said the retailer.

“He did this despite there being a variety of other internal routes available to address his concerns and very clear guidelines – in common with many other companies – on employees’ handling of internal information.”

M&S said that the employee in question had refused to commit that he would not leak company information in the future.

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