The GMB union says the new contracts remove all paid breaks and impose longer unpaid breaks, which will see staff working extra and longer shifts for no more pay.

A total of 2,000 workers are affected - approximately half the workforce - and anyone who rejects the change will be sacked and rehired on the worse contract, the union says.

The majority of those affected are nursing staff working on the wards. There are concerns that most in these roles will be unable to take their full breaks due to patient care and staff shortages, increasing the likelihood of higher unpaid hours across the trust.

Rachel Dix, GMB organiser, said: 'This move from the trust managers is a demoralising and unfair attack on their terms and conditions.

'GMB members have been absolutely clear they will not accept this attack on their well-earned break times and will stand up to the appalling threat of fire and rehire.'

‘It's time for the trust to back down on these proposals before hospital services are badly disrupted.'

In response, a Barnsley Hospital spokesperson, said: ‘These proposals would bring the trust into line with almost all other NHS hospital trusts and with the national NHS terms and conditions that were agreed some years ago by trade unions and the NHS. It would provide more staff on duty for patients and reduce reliance on temporary staff. Evidence shows this would improve patient care and safety, support staff wellbeing, reduce healthcare costs and improve staff retention.

‘The trust has undertaken eight months of consultation with affected staff and trade unions and these discussions continue. The GMB has not notified the trust, as it is required to do, of its intention to undertake a ballot for industrial action.

‘Staff wellbeing is a priority for the trust. Ensuring colleagues have adequate rest breaks is essential to mitigate fatigue and maintain health. We remain committed to appropriate breaks in line with best practice and national NHS terms and conditions.

‘This process was driven by our commitment to fairness and consistency, addressing long-standing informal arrangements and variations in how breaks were taken across departments, which raised concerns about equity among other staff groups with unpaid breaks.'

The indicative strike ballot will close on Monday (2 February).