NHS campaigners have called on the Mayor of Greater Manchester and local health chiefs to support striking hospital workers.

Keep Our NHS Public has written to Andy Burnham and to Bolton Clinical Commissioning Group (CCG) asking them to “step in” and ask the trust to resolve the dispute.

The dispute has been ongoing for several months now and the cleaners, porters and caterers at the hospital are asking for a pay rise.

Hugh Caffrey, secretary of the Greater Manchester branch of Keep Our NHS Public said: “We support what the staff are doing. Their strike is a challenge to privatisation and we support their action.

“If they win, and we hope they do, it further undermines the attempt to undermine the NHS.”

The striking staff ­— among the lowest paid in the hospital ­— are employed by iFM Bolton, a wholly-owned subsidiary company of Bolton NHS Foundation Trust and are on a separate contract to the rest of the staff at Royal Bolton Hospital.

NHS staff received a pay rise in April but this was not mirrored by iFM. Staff at iFM now earn less than staff doing the same jobs in neighbouring trusts.

UNISON, the union representing the workers says the pay rise is worth around £2,000.

iFM bosses have said they are willing to negotiate with the workers and have already had two of their offers rejected.

The Greater Manchester Combine Authority (GMCA) received the letter on Friday and a spokesman said Mr Burnham will be responding.

A spokesman from the GMCA said: “The Mayor of Greater Manchester, Andy Burnham, is aware of the ongoing dispute at Royal Bolton Hospital. He received correspondence from Keep Our NHS Public late last week and will reply in due course.”

Bolton CCG declined to comment. Bolton iFM did not respond to a request for comment.