Duncan tipped for Cabinet post

Brendon Grylls will be replaced in the Barnett Government ministry by another Nationals MP - but the Premier will not guarantee the party will keep the Regional Development portfolio.

Mr Grylls said the allocation of portfolios was ultimately a matter for his successor as leader and Colin Barnett to thrash out but he believed Regional Development should continue to be held by the Nationals leader.

"Those two things go hand in hand," Mr Grylls said.

Mr Barnett said portfolios were still to be determined and would not be discussed until the Nationals picked a new leader.

He would aim for a "minimal" reshuffle of portfolios.

"The portfolios will be something I will determine with the deputy Liberal leader (Kim Hames) and the (new) leader of the Nationals," he said.

The alliance government agreement between the Nationals and Liberals provides for three Nationals ministers.

Mr Barnett said it was a matter for the Nationals to choose who would replace Mr Grylls.

Kalgoorlie MLA Wendy Duncan, the Legislative Assembly deputy speaker, is widely tipped to get the job.

The Nationals' 12 MPs will meet at Parliament House this morning to establish a process for the leadership transition.

It is likely Mr Grylls will continue as leader through to the end of the parliamentary year on December 5.