Pike River mine illegal by Australian standards - Key

Prime Minister John Key said the one-entry Pike River mine would have been illegal by Australian standards, and he expects changes will need to be made to New Zealand's mining practices.

In an interview with The Australian newspaper, Mr Key said changes would be made to mining safety laws after 29 men were killed at the West Coast coal mine last year.

A Royal Commission of Inquiry is to investigate the disaster at the West Coast mine, looking at whose responsibility it was, whether it could have been avoided and if there were systemic problems with implications for other underground mines.

Although Mr Key told the newspaper he was not in a position to "give a full response" on mining safety until after the inquiry, he said "we do have to ask the question" about safety standards.

"We have taken an interim review of our mines to check for safety but long term, there'll need to be other changes, I suspect," he said.

When questioned today, Mr Key told news media he was not saying New Zealand's mining standards were lower than those across the Tasman.

"I'm saying they are different from Australia, the way the mine was consented in New Zealand is likely to be legal, but that's a matter for the Royal Commission of Inquiry to look at, it's not for me to pre-judge what they might find," he said.

"From a construction perspective, that mine would not be consented in Australia and was consented in New Zealand.

"From a safety standard perspective that's a matter for the Royal Commission to tell us whether they think there are proposed changes or whether there is a necessary need for changes in safety standards in New Zealand."

Mr Key previously said he had he had no reason to doubt New Zealand's standards.

"I have no reason to believe that New Zealand's safety standards are any less than Australia's, and in fact our safety record for the most part has been very good," he told news media in the days following the disaster.

The Labour Party said Mr Key had done a "total about-face" on the issue.

West Coast-based Labour MP Damien O'Connor said it was difficult to understand why Mr Key had made the comments to an Australian newspaper, but had not told the families of the Pike River victims.

"If John Key is confident enough to make such an announcement, despite previously stated our safety standards were the same as Australia's, then he should do something about the current situation in New Zealand where no underground mining regulations exist."

Leader Phil Goff also spoke out against the comments.

"He said it was dangerous to make comments about safety ahead of the Royal Commission, that was just a month ago," he said.

"This is a total change in direction. If he's got information then surely he should give that information to those most immediately involved first and then act of it."

The Engineering, Manufacturing and Printing Union (EPMU), which represents miners, also called for action.

"Now we know that the government has identified problems with safety standards, we can act now to fix them," EPMU national secretary Andrew Little said.

"We don't need to wait for the Royal Commission's decision. And we can spare the families further pain and suffering."

Mr Little said there was plenty of international evidence and expertise available to start making changes to mine safety regulations now.

An audit by two Australian mining experts, issued last month, found two New Zealand mines were not fully compliant with health and safety regulations, but found no evidence of imminent danger at any of the four mines investigated.