Origin Energy Ltd says US energy giant ConocoPhillips has received Foreign Investment Review Board (FIRB) approval for the companies' proposed coal seam gas joint venture.

Origin and ConocoPhillips agreed last month to form the joint venture to commercialize the Australian energy retailer's coal seam gas assets through a liquefied natural gas (LNG) development.

The joint venture proposes the development of four LNG trains, or processing plants, in Queensland, with production from the first two, 3.5 million tonne-a-year trains expected by 2014.

Origin reaffirmed Thursday that ConocoPhillips would provide an initial US$5 billion ($A7.42 billion) payment on settlement of the transaction.

Origin said that, given the size of the transaction, settlement would take place over two consecutive business days. It was expected to be completed in about a week.

Origin said ConocoPhillips also would pay a fixed contribution of A$1.15 billion to carry Origin's share of costs to a final investment decision (FID), expected in 2010.

ConocoPhillips also would provide payments of US$500 million (A$742.45 million) at the point that each of four proposed LNG trains are approved, to partly carry Origin's share of costs.

Origin said it would inform the market on completion of the initial US$5 billion transaction, when it also would provide shareholders with further information regarding the timing of the A$1.5 billion capital management program.

(C) 2008 Asia Pulse Pte Ltd.