Thousands of New Zealand public servants and union members have voiced their opposition to austere pay guidance issued last week.

The guidance specified there would be no increases for workers above $NZ100,000 ($A92,700) and no extra for those earning above $NZ60,000 ($A55,640) except in limited circumstances.

Both Finance Minister Grant Robertson and Public Service Minister Chris Hipkins said the policy was intended to show "restraint", suggesting the matter was closed.

Unions have hit back, saying the guidance constituted a starting point in pay negotiations - and attacking their position as bad faith.

On Tuesday morning, the three top ministers met a delegation of union leaders in the Beehive in Wellington, with Council of Trade Unions boss Richard Wagstaff saying the government heard their frank feedback.

"We made it crystal clear how unhappy and angry union members are feeling in response to the policy announcement," he said.

Mr Wagstaff suggested the government had already accepted its position was untenable.

"There was absolute agreement that bargaining will be in good faith without pre-determined outcomes," he said.

"It was also agreed that there is scope to discuss cost of living increases in negotiations ... with higher increases for low paid workers and that there is no pay freeze."

Both sides have agreed throughout on the need to focus pay rises to the lowest-paid workers, who earn under $NZ60,000 ($A55,640), to target inequality.

Australian Associated Press