NEW ZEALAND (From news reports) -- Oji Fibre Solutions Penrose mill is permanently closing, the E tū union says.

Union spokesperson Joe Gallagher said the mill's last day would be 18 December and at least 72 workers at the mill had been affected.

Oji Fibre Solutions said it was considering closing its Penrose mill, partly due to high power prices. Up to 75 workers would be affected.

Earlier this month, 230 workers at Winston Pulp International were told the sawmill and pulp mills near Ruapehu were both closing for good.

About 30 workers attended a meeting at the Penrose milll on Wednesday morning.

Work at the site was paused for 24 hours.

The company's announcement pack given to workers, said this was to give staff time to go home, digest the news, and talk to their families and loved ones.

It said it has no choice but to cease operations at its Penrose mill after suffering a three-year pattern of losses.

"We see no prospect of the situation improving, and we cannot continue the way we are now.

"We've looked at every lever we could pull. We've considered a very thorough submission put forward by your unions and the questions raised by individual employees.

"But at the end of the day, there's nothing we could find that would make enough of a difference."

The company said the mill had a skilled workforce and leadership team, and the closure decision wasn't to do with them. It would be offering CV advice and interview technique workshops to staff.

In a statement, it said it would continue to collect wastepaper and recycle about 90,000 tonnes of cardboard a year at the Kinleith Mill, near Tokoroa. Other wastepaper would be sent to an Oji Group mill in Malaysia.

Shift electrician Maurice Upton, who has been at the mill for 20 years, said staff were hoping it could be saved.

He said the Penrose operation was one of the most efficient mills in the country but couldn't compete with a the new mill the company had built in Malaysia.

Following the news of the closure, Upton said that emotions were running high.

"I'm just sitting here contemplating the future. We were pre-warned about six weeks ago this could happen but now we know for sure, so the reality has set in. I guess I'm a little shocked like some of my colleagues. It's a sombre mood."

Upton said he did not believe the workers were any less efficient than any other plant. The mill had been suffering from energy costs "and the like" but it was common for other companies, too.

He said the future looked a bit unstable at the moment.

Some colleagues had said they would go to Australia for stability but others would be looking for work closer to home.

Labour leader Chris Hipkins called on the government to do more about electricity prices following the confirmation of closure. "I think this is a sign of market failure and something the government should get on top of very quickly," he said.

Ahead of the meeting, Gallagher said workers were resigned to being told there was a closure.

He said a combination of factors was behind the current situation, including power and gas prices, but also a lack of past capital investment.

Gallagher said $50m in capital upgrades would be needed if the mill were to remain open.

"They ruled that out as a solution.

"I think the signal is quite clear that the announcement today will be a closure.

"We've got to support these workers and it's a pretty tough time, leading up to Christmas, to lose your job."