A group of men unhappy at being paid less than their female counterparts have won their equal pay claim in what is thought to be a landmark case.

Around 18 workmen - including carpenters, plumbers and caretakers - took employer the University of Wales, Trinity St David (UWTSD) to an employment tribunal claiming they were being paid less than female counterparts on the same pay scale, such as secretaries and office workers.

Their bosses had insisted the difference was not due to gender and was because of changes due to the men's contracts. But in an unexpected U-turn, the UWTSD's legal team told a hearing in Cardiff they would no longer be contesting the equal pay case.

Tradesman Robert Cooze, 50, said he and his colleagues were over the moon.

"We didn't want it to come to this really but we're glad common sense has prevailed," said Mr Cooze, who lives and works in Swansea. "It's been admitted that we have been discriminated against.

"With all due respect to our new employers, Trinity St David, this is completely new to them and is a historical issue.

"I would like to think that they have had some input into this.

"We are just so relieved and can get on with our ordinary working days now.

"At certain times it did get us down because in the past ... we felt like we weren't being listened to.

"I just hope it hasn't soured any relations between us and our new employers."

It is believed to be the first time that such a large group of men have launched legal action in Britain claiming sexual discrimination. Although tribunals brought by men are not unheard of, the case involving the Welsh university workers has been described as "very unusual" since the majority of unfair pay claims are brought by women.

All the men were originally employed by Swansea Metropolitan University which merged with the University of Wales Trinity Saint David in August last year.

They were on grade 3 on the university's pay scale - but the dispute arose when their contracts changed. Previously, the men had been on a minimum 45 hours per week contract until new regulations sought to standardise all workers' contracts to a 37 hour working week instead.

Fearing the drop in hours would cause problems, university bosses said they would guarantee the men the extra eight hours but class it as overtime pay.

However when the new system was put in place, the men said they realised their hourly rate was less than women who were on the same pay scale.

Mr Cooze added the group were also incredibly grateful to Belfast-based solicitor Paul Dorran and QC Caroline Musgrave for their work on the case.

"They've been absolutely immense throughout all this," he added.

In the meantime, both parties are going to work out an agreement on the payout. Although the workers are not applying for damages for injury to feelings, they are seeking back pay plus interest and their legal firm - who operate on a no-win no fee basis - are to apply for costs.

There could also be further costs to the university in the future too.

Previously, a separate group of seven workmen said they would launch their own legal bid if their colleagues were successful with their claim.

If all 25 end up being successful it could result in a total payout of around £750,000 - with each worker winning around £30,000 in back pay.

UWTSD explained it changed its position following evidence given at the tribunal by Professor David Warner at the hearing today.

Prof Warner was the vice-chancellor at the now defunct Swansea Metropolitan University.

A university spokesman said: "We came to the view the original claim presented by staff to the former Swansea Metropolitan University had due merit and, as a result, an appropriate remedy should be agreed and actioned.

"The employment tribunal related to events that occurred more than seven years ago at the now dissolved higher education corporation Swansea Metropolitan University and several years before its merger with the University of Wales Trinity Saint David which took place in 2013.

"The University of Wales Trinity Saint David had no involvement in the decisions that were made by Swansea Metropolitan University in 2007.

"This was a complex case and we are very disappointed the new university now has to deal with, in an appropriate manner and with due care, the consequences of historical decisions."