WITH Brendan Nelson's leadership under growing pressure, Liberal MPs eager for a change will know Peter Costello's intentions sooner than expected.

The publication of the former federal treasurer's memoirs, regarded as final confirmation of whether he will go, has been brought forward from October to mid-September.

Nelson's ham-fisted handling of climate change policy over the past month has greatly undermined confidence in his leadership among those on both sides of the debate within the Liberal Party.

Several sources confirmed yesterday that everyone was waiting to see what Costello would do before other options were considered.

If Costello stayed, he would become leader. If he went, it would be up to others to put their hands up and force a spill.

"Everyone thinks it's just hopeless at the moment but we can't do anything," one frontbencher said, of waiting for Costello.

The Seven Network reported last night that Costello knocked back a job with the London-based World Gold Council, worth £1 million, or $2.1 million, a year. The Herald learnt subsequently that Costello rejected the job in February because it was not to his liking and he had reservations about moving abroad.

It is understood he was offered the position by the former NSW National Party MP and former Liberal Party office holder Robert Webster, who is a director of the international headhunting agency Korn/Ferry.

One corporate source said offers "have been drying up left, right and centre lately" and there was a good chance Costello would stay.

But political confidants of the former treasurer believe otherwise. Those closest to Costello insist he still intends to leave politics after his book is published but he has been lobbied by many in recent months to reconsider.