Tens of thousands of Morrisons supermarket workers face being hit by a pensions shake-up branded “blatant profiteering”.

The Unite union has accused the grocer of “fleecing” staff by proposing to reduce the percentage it puts into their retirement funds, but getting them to make up the rest itself. Unite claims it will save Morrisons - bought by a US private equity giant for £7billion in 2021 - between £10million and £14million a year.

The union represents 1,000 warehouse workers in Cheshire and Wakefield but says the proposals apply to 40,000 hourly paid workers. Unite general secretary, Sharon Graham said: “Pensions villain Morrisons is planning to fleece workers by hiking their pension contributions while slashing its own contributions to the scheme. This is blatant profiteering and a disgraceful new low for this well-known supermarket.”

Morrisons’ current pension contribution for those under its auto-enrolment scheme is 5%, with staff putting in 3%. The supermarket wants to flip that on its head. By March 2025, it would mean the company putting in 3% - the bare minimum allowed - and workers 5%. As a result, workers would end up with less take home pay to live on.

Unite says some staff, unable to afford it, are set to pull out of the pension scheme altogether, leaving them vulnerable when they retire. The union claims Morrisons is using wider changes to the enrolment pension scheme - not yet law - as a “Trojan horse” to bring in the cuts.

In a statement, Morrisons said: “There will be a formal consultation process lasting until early January 2024.”

Insiders said the firm’s overall auto-enrolment bill was likely to rise as, under proposed pension law changes, employers will pay contributions from the first £1 workers earn, rather than the current £6,240 lower limit.