Prime Minister John Key is facing Opposition calls to clarify whether his pledge to not legislate against court decisions upholding Maori claims to rights and interests over water includes proprietary or ownership rights.

The call comes after Mr Key said his Government could in theory legislate to say no one owned water in the event a court case resulted in confusion on that issue.

After a late-night discussion with Mr Key on Wednesday, Maori Party co-leader Tariana Turia said she had secured a pledge from Mr Key that should a future court decision find that Maori did have a proprietary type right over water, the Government would not legislate against that.

Asked yesterday whether the pledge applied to any proprietary rights upheld by a court, Mr Key said: "I think that would be right but it would depend what you meant by all of those things. I think it's important to not confuse all of those things."


Mr Key was also asked whether, in the event a court case resulted in a situation where there was confusion over the nature of rights upheld, his Government would legislate to say that no one owned water, in the way it did over the foreshore and seabed issue.

"In theory, but one would hope it wouldn't come to that," he said. "At the end of the day that's not the preferred option."

In Parliament yesterday, Labour deputy leader Grant Robertson asked Deputy Prime Minister Bill English whether the pledge not to legislate would stand whatever rights a court may decide Maori had in terms of water.

Mr English did not directly answer that question but was later asked whether he would rule out passing legislation in response to a court ruling that found an iwi owned a waterway.

He responded by saying: "Well yeah, we've said we're not going to legislate over rights and interests."

Mr Robertson later told the Herald it was clear that Mrs Turia had walked away from her meeting with Mr Key this week with the impression the Government would not legislate against any court decision upholding Maori proprietary rights over a waterway.

But Mr Robertson said Mr Key's comments and Mr English's reluctance to answer direct questions yesterday cast some doubt on that.

"We now have some confusion about that. The Government needs to make its position clear. The big decision they have to make is is there a limit to what they're prepared to simply leave as being a court decision?"