health reporter,bolton(weastar times):::The trust, which runs the Bolton Hospital, has had to borrow £8m from the government to pay wages and needs to save £38m over the next two years.
The trust said it may dismiss more than 1,600 staff, then re-hire them on new terms and conditions.
Unison said some nurses were "very upset" and had been in tears.
Trust chairman David Wakefield said patient care would not suffer and managers were hoping to avoid compulsory redundancies, but some would be inevitable.
The contracts of 1,685 nursing, midwifery and support staff as well as and medical and dental personnel could be affected.
A leaked internal email from the Bolton NHS Foundation Trust said it might be possible to deal with "some proposed changes by agreement."
But the trust may consider "terminating existing contracts" with an immediate offer to re-hire people "on revised terms and conditions of employment".
Unison regional manager Steve Stott said: "Unison is committed to working with management to minimise job losses, but at the same time will consult its members on all available options open to them up to and including industrial action in order to oppose compulsory redundancies."
Janine Dyson, from the Royal College of Nursing, said: "The terms and conditions in the NHS are negotiated nationally.
"They make sure there is provision that you get the best quality, highest skilled, best trained, up-to-date staff in the NHS, so to dismiss and re-engage on alternative terms and conditions puts all that under threat."