Sainsbury’s has spent £100 million this year increasing salaries, but it wants to retain the flexibility to manage its wage bills rather than lock itself into higher pay levels set by a third party.

“As a listed business we always try to balance the needs of all our stakeholders, including our customers, colleagues, suppliers and shareholders,” Sainsbury’s said.

“The vast majority of Sainsbury’s shareholders are UK pension funds and private investors – including Sainsbury’s colleagues – for whom dividends are vitally important.

“We understand that households are counting every penny right now, and that’s why by the end of the year we will have spent over £500 million to keep prices down on the essential items our customers buy the most.”

City investors including HSBC, Legal & General Investment Management and Fidelity International as well as retirement fund Nest and the Brunel Pension Partnership are already part of the coalition behind the resolution that comes as family budgets are squeezed by surging inflation.

Back in April, Sainsbury’s raised pay for its 171,000 direct employees across more than 1,400 stores in the UK to the living wage, which is independently calculated for the Living Wage Foundation charity, of at least £9.90 an hour outside London or £11.05 in the capital.

However, it has not made the same commitment to contractors.

Over half of the FTSE 100 are among the more than 10,000 accredited living wage employers. However, none of the big supermarkets are among them.

Rachel Hargreaves, a campaigns manager at ShareAction, said: “There is no excuse for a highly profitable company with multimillion-pound executive salaries refusing to guarantee all its staff, including subcontracted workers, a basic standard of living.”