Plans to cut millions of pounds from health services in Northern Ireland could face a legal challenge from trade unionists.
Extra money has been found from within the wider public sector to limit cuts to front line services which once threatened to reduce the number of hospital beds and delay operations.
But a union representing thousands of healthcare workers urged trusts responsible for implementing the savings to challenge the Department of Health.
Unison said: "If you do not do so, we will challenge you using all legal means at our disposal, a process that has already begun through the complaint Unison has submitted to the trust for the major breaches of your equality duties."
Senior representatives of the union attended public meetings of trust boards across Northern Ireland on Friday.
They told board members: "You are meant to act as guardians of the health service as members of this Trust Board.
"Today, we are repeating our call to you to stand with us to challenge the lack of funding for proper health and social services in Northern Ireland.
"You have seen over the past six weeks that we are prepared to fight for it, and the public is prepared to fight for it.
"It is time that this Board, both executive and non-executive alike, demonstrated that you too are prepared to fight for the public you are appointed to serve.''
Trust boards are tasked with drawing up detailed plans for achieving any savings proposed by the Department.
The Department has said extra funding announced recently will reduce the projected £70 million savings needed by the end of the financial year.
Of the proposed £31 million adjustment affecting front line services only £3 million will now be required, the Department has said in a letter to health trusts.
The rest will be found from less visible or back office services, termed "low impact" by the department, which do not affect the public as directly.
But unions have expressed deep unease about the plan.
A statement from the Department said it noted Unison's comments but the position remained as set out in the letter to trusts.