Maori claims of water ownership need to be resolved before asset sales go ahead to ensure the Government gets the best price, experts say.

Berl chief economist Ganesh Nana told an urgent Waitangi Tribunal hearing on the issue that uncertainty was the last thing that investors needed.

"The main message is that the Crown needs to ensure that the uncertainty around water rights or access to water or remedies needs to be minimised [as much] as possible if the share sale is to be a success."

Whether water could be owned was not really relevant, Dr Nana said. "The important thing is who has the right to manage that water, how is that water managed and used, that is the important thing."

An essential tool for the management of water was price, he said.

Hydro-electric companies now use water free-of-charge.

A water charge would "inevitably" push up power prices, but the point of putting a price on water was to ensure the right decisions were made about its use.

Dr Nana said the income from selling off the assets was insufficient to compensate for lost dividends.

Auckland University professor Jane Kelsey also appeared before the hearing yesterday.

She argued that not settling the dispute with Maori would leave the Government open to complaints by investors under international agreements.

"The threat from an investor to take such action could result in the Government backing off implementing the Waitangi Tribunal's recommendations."

Historically governments had put other interests ahead of Maori.

The Government would have to consider selling down its own majority shareholding to meet its obligations to Maori, or buy shares back from other investors, Dr Kelsey said.

"The Government might decide to fight the matter in a tribunal which could take a very long period of time and cost a lot of money for an outcome that is extremely uncertain."

- © Fairfax NZ News