The Co-op has won a case brought against it by former procurement director who alleged she had been unfairly dismissed for whistleblowing.

The employment tribunal in Manchester ruled in favour of the Co-op in the case brought by Kath Harmeston.

Harmeston, who acted as procurement director between April and September 2014, alleged that she had been unfairly dismissed from the retailer after she blew the whistle on improper corporate governance.

She was seeking £5m in damages but the tribunal ruled she was not unfairly dismissed and the retailer did not subject Harmeston “to any other detriment” on the grounds of her whistleblowing claims.

However, the tribunal did find that the Co-op deliberately failed to pay Harmeston’s expenses claims “within a reasonable period”.

A statement from the Co-operative said: “The Manchester employment tribunal has dismissed the whistleblowing claim brought by former procurement director, Kath Harmeston, against the Co-op.

“We are glad that the tribunal has supported our view. We fought this action because it was be right thing to do and in the interests of our members.

“We would like to thank our members for their support.”