While exact details remain unclear, it is apparent the Maui partners - Shell New Zealand, Todd Energy and OMV Petroleum - are discussing with the Crown ways of extracting more gas from the fast depleting, formerly giant field.

Options being considered are understood to include the government forgoing its energy resources levy and effectively paying that to the partners; renegotiating the contract to allow further exploration to become economic; or "swapping" Pohokura gas for Maui gas to ensure the government can meet its obligations to Methanex, NGC and Contact Energy until the end of the Maui contract in 2009.

However, all these will mean significantly increased wholesale gas prices, as the Maui partners, who happen to be the Pohokura parties, will only agree to make economically attractive moves.

Some New Zealand media have speculated that these talks are centred around assuring thermal power generators and other big users, including perhaps even Methanex, of sufficient gas supplies being available until Pohokura is brought onstream in mid-2006.

There is also the virtual necessity of encouraging as much exploration as possible, certainly for at least the next three years, to hopefully ensure explorers find the fields necessary for a post-Maui age and thus avoid costly LNG imports, probably from Australia's North West Shelf.

Sticking points are likely to be the difficulty of changing the long-standing Maui contracts and the pricing of "new" gas deemed to be outside the economically recoverable reserves (ERR) determined early this year by independent expert Netherland Sewell and Associates.

Too high a price and big users - particularly Methanex but also including thermal power generators during warm wet winters - will be unable to buy extra Maui gas. Too low a price and the partners will not proceed with any more exploration within the Maui licence, such as the rumoured Ihi prospect.

There are no easy answers, as Methanex president Bruce Aitken told ERN earlier this week, when he said one of the biggest issues for the Kiwi gas market was a lack of transparency and that no gas was traded or prices reported on a daily basis, as in the US or Australia.