The Co-op's insurance company was yesterday accused of betraying the ethics of the movement by allegedly sacking more than 2,000 financial advisers and offering them new jobs under different terms and conditions.
The retail union Usdaw said its members were "totally shocked" by the decision, which the union added had been taken to turn around the company's trading position in the fiercely competitive financial products market.
The Co-operative Insurance Society (CIS) denied it was sacking its financial advisers and said it was "disappointed" with the union's reaction.
A company spokesman said sales staff used to spend half of their time on administration and customer service duties which was an out-dated way of operating.
"We are taking the administrative burden away from them which we don't feel is unreasonable, given that our competitors have abandoned their sales force.
"We are giving them new terms and conditions and contracts of employment. We want all of them to sign these and stay with us in what we feel will be a very bright and promising future."
John McGarry, North West divisional officer at Usdaw, said: "We're very disappointed that a company that trades so heavily on its ethical policy should decide to take this sort of action especially as we had arranged a meeting at Acas in August to try and thrash out a way forward.
"We will continue to have a robust dialogue with CIS, as we have had a long standing and productive relationship with them, and we will continue to make the case for meeting at Acas."
CIS chief executive David Anderson said: "Although we are introducing new service options for customers our financial adviser sales force remains an integral and fundamental part of our plans for the future.
"By implementing these plans we will also be making a major commitment and investment in our sales force, which itself demonstrates our confidence and belief in a channel that has been abandoned by our competitors."
The CIS said in a statement it was on target to realise the benefits of its modernisation programme.