Turnbull can break the deadlock:Hewson

Switching to Malcolm Turnbull gives the government the opportunity to reset the economic agenda and break the reform deadlock, former Liberal leader John Hewson says.

Mr Turnbull put the handling of the economy at the centre of his challenge to oust former prime minister Tony Abbott last Monday.

Dr Hewson said it is about marketing the message that gives a better explanation in a very uncertain global economy.

He said the government must focus on an objective, like doubling the nation's productivity by 2025, and then go through each of the policy areas to explain what needs to be done, whether it is the reform of industrial relations or tax or energy and energy efficiency.

"You need to reset the agenda because we can't go on with this game where one side (of politics) proposes something and the other side immediately says no," Dr Hewson told Sky News.

Former Labor state treasurer Michael Costa said if Mr Turnbull and his new economic team - that will be announced later on Sunday - can sell the economic message, then the change to Mr Turnbull would be worthwhile.

"But I'm sceptical," he told the Ten Network.

He said the government still faces a hostile Senate and the budget position is worse than when the coalition came into government with debt heading towards half a trillion dollars.

"We've got the global economy looking worse," he said.

Scott Morrison is widely tipped to move from the social services portfolio and take over the role of treasurer from Joe Hockey.

It is still not clear whether Senator Mathias Cormann will remain finance minister.

"I will continue to do my best in whatever capacity the leader sees fit," Senator Cormann told Sky News.

He agreed the government should be explaining the economic challenges the nation is facing.

As an exporting nation, the government has got to continue to focus on doing everything it can to ensure it is as competitive internationally as it can be, while improving productivity and reducing the cost of doing business.

"I agree we can always do better," he said.