Under the plan, proposals to move NHS staff into separate companies, known as SubCos, will be paused and any future transfer of NHS workers will be approved only where there is clear union support, as well as protection of NHS terms and conditions.

In the letter, Glen Burley, financial reset and accountability director at NHS England, said: ‘This is about shaping the future of the NHS workforce, ensuring fairness, and giving staff and their representatives confidence that their voice matters in decisions of this kind. It is also about providing clarity and consistency for trusts as they navigate challenging financial and operational pressures.

‘We will shortly consult on these changes. We want to work with you, with staff and with unions to agree the proposed changes and the detail of how this will work in practice. It is also about ensuring we strike the right balance between protecting staff and preserving the freedoms of foundation trusts to innovate in ways that strengthen, rather than fragment, the NHS.'

In response, Unison general secretary Christina McAnea, said: ‘Today's announcement is a positive step in the right direction and shows ministers are listening to the union's warnings.

‘The NHS relies on support staff to keep hospitals clean, safe and running efficiently. They deserve the same pay and conditions as other health workers. 

‘Subsidiary companies have never been the right way to deliver NHS services and Unison will keep campaigning for further change. Any trusts considering outsourcing need to think again and work with their staff on better ways to save money or reorganise services.'