BG Group's Aussie target Origin Energy today unveiled a 20% rise in full-year profits to A$443 million (£207 million) but predicted slower growth in the months to come.

The unexpectedly gloomy forecast for the next year will be a boost to BG's prospects. Origin says earnings should rise by at least 10% in the coming year.

It has rejected a A$13.7 billion hostile bid from BG, saying it undervalues the company's coal gas assets. Origin managing director Grant King says shareholders will benefit more from a partnership to develop its assets. However, the rejection is seen as a gamble for King, who has yet to unveil an alternative to the British offer.

He is said to have been in talks with BP and Royal Dutch Shell about a possible deal. Origin has said it will present shareholders with details of its proposed coal-seam gas partnership at least a week before BG's offer closes at the end of September.

BG is keen to add coal gas reserves to feed into an A$8 billion project it has in Australia that is aimed at Asian markets.