Finance Minister Bill English can expect a hostile reception from union delegates when he addresses the Public Service Association on Tuesday.
The union has been a vocal opponent of public sector cuts and national secretary Brenda Pilott says Mr English will face questions about the government's management of the public service.
"I think they (the delegates) will want to send him a strong message about the reality of public sector cuts on the ground.
"These are being felt acutely by our members in terms of job losses, unfilled vacancies, unsustainable workloads, loss of expertise, job security concern, and plummeting workplace morale," she said.
Ms Pilott says the 160 delegates, representing around 58,000 members, will also want some assurances over the future of the state sector.
Mr English will address the conference in Wellington and will also face questions from the floor.