Broadband company Chorus will launch an independent review, after a Government investigation found dozens of migrant workers employed with subcontractors had been exploited.
"We are absolutely determined to make sure that all the people who work on our behalf are treated fairly and within the law," Chorus chief executive Kate McKenzie told Newshub.
"We want to take whatever steps are necessary to ensure that's the case."
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The Labour Inspectorate investigation found 73 subcontractors rolling out broadband networks throughout Auckland had breached minimum employment standards.
"Breaches we observed to-date included contracting employers failing to maintain employment records, pay employees' minimum wage, holiday entitlements, and provide employment agreements.
"Many of these employees represent a vulnerable section of the New Zealand workforce that often aren't aware of their minimum employment rights, and are concerned with their visa status."
Ms McKenzie says she felt "very disappointed" by the results of the Labour Inspectorate findings.
"We have on many occasions worked with our contracting partners to try to ensure that all of the employment arrangements are within the law and fair," she said.
"We want to make sure that somebody independent can come and have another look to make sure that we haven't missed anything."
She said she expects the company's contractors to cooperate with the independent review.
Minister for Workplace Relations and Safety Iain Lees-Galloway said the findings of the investigation are "simply not acceptable and it is not welcome in New Zealand workplaces".
"It is critical that our workplaces are free of the kind of exploitative practices that the Labour Inspectorate has found," he said.
"It is bad for workers, it is bad for our reputation and ultimately, bad for our economy."
E tū communications industry coordinator Joe Gallagher says the findings are alarming, but not surprising, saying the union has "known about the effect of this contracting model since they started it".
"This model of contracting and sub-contracting has allowed Chorus to pass the buck, resulting in contractors exploiting their workforce to keep to budgets and schedules," Mr Gallagher said.
"The Government now has to move as quickly as possible to fix this any many other problems with the UFB roll-out. We are optimistic that this Government understands the issues and wants to fix them, but time is of the essence."
MBIE said the Labour Inspectorate is continuing with its investigation with a "view to taking a wide range of compliance actions".
In August, MBIE named and shamed New Zealand employers caught exploiting workers in a published list. It included Burger King's parent company, Antares Restaurant Group, which was barred from hiring migrant works for a year.
A Burger King worker wasn't paid for extra hours during her shifts, and established that altogether she was getting below the minimum wage.
Earlier this year two former Auckland Domino's Pizza franchise owners - one in Henderson and one in Te Atatu - were found to have underpaid staff by more than $54,000.
Government figures released to Newshub in June showed a significant increase in complaints of employers exploiting workers and breaching laws in the hospitality industry.