Photo: ©  2010 AAP/ALAN PORRITT

Like Brendan Nelson, the man he ousted, Turnbull has decided to pursue a new career rather than hang around the backbench under the cloud of deposed leader. 

He broke the news on Twitter, before talking with the media.

"Having become leader and then that having come to an end in some fairly trying circumstances, I think the best thing is to move on as a former leader," he told Sky News.

The one time merchant banker lost his leadership to Tony Abbott last December after the party was split over climate change.

It's not yet clear what the future holds for Turnbull, though it could be something big.

His predecessor was appointed Ambassador to the European Union and NATO a year after being deposed.