Two more NHS trusts face equal value claims following the victory last week of more than 200 female domestic and catering workers granted parity with male porters at Hartlepool General Hospital.

The workers were represented by the GMB union, which claimed its victory would apply across the country at a potential cost to the NHS pay bill of an extra£40m a year.

Hartlepool and East Durham trust, which disputed the claim over the last two-and-a-half years, has now agreed pay rises of up to 11 per cent for the women, at a cost of£400,000 on its annual wage bill. The agreement, which will boost individual pay by between£9 and£18 per week, was reached just two days before a series of employment tribunal hearings was due to start.

Hospital GMB chief steward Emily Waller said the victory was already being followed up with similar claims against hospitals managed by Newcastle City Health and Carlisle Hospitals trusts.

'This has sent out a warning to nearby trusts that you cannot have people working alongside each other who do the same work yet one section is deprived of bonuses of up to 20 per cent,' she said.

Human resources director Ian Palfreeman said: 'We are pleased that staff have agreed to accept our proposals.

'We are fully committed to equal opportunities and are very happy to have been able to introduce new improved payment systems and working practices for the benefit of the trust.'

A Newcastle City Health trust spokeswoman said she had heard the GMB was due to pursue a similar case against it and Carlisle Hospitals trust.