Methanex has committed $A50 million so far to the project; has undertaken two engineering packages; and has selected a preferred bidder for the construction of the two-million tonne per annum plant.

Also, a finance package is expected to be finalised and offered to institutions later this month.

However, Aitken said the Methanex board was not expected to give its final approval for the world's biggest single-train methanol plant until early next year, Aitken told EnergyReview.Net in Auckland before flying out to board meetings in Canada.

"We need to have the financing in place, the construction contracts in place, every major issue tied up before going to the board for that final approval."

Methanex last year signed a memorandum of understanding with the North West Shelf participants before concluding a more detailed gas sales and purchase agreement. The newPilbura plant would use the latest "syngas" technology and options existed for future expansion and the construction of other plants, which could manufacture other products using the same syngas technology.

Capacity could also be doubled by the construction of a twin WA plant if Methanex decided to permanently shut down all or some of its New Zealand operations, which have the capacity to produce up to 2.4 million tonnes a year from three trains, later this decade.

This would ensure Methanex continued meeting or expanding its methanol market share in a growing Asia-Pacific region. The ideal scenario, however, would be to have plants in Australia and New Zealand operating in tandem, Aitken concluded.