Malcolm Turnbull has called on Prime Minister Scott Morrison to call the election as soon as possible in 2019.

"My view is that it would be manifestly and in the best prospects of the Morrison Government to go to the polls as soon as it can after the summer break," he argued this morning.

"In fact, my intention, and Scott's intention for that matter, prior to my being removed as prime minister was to go to the polls on the March 2."

This is the thinking behind that proposal, and why he is speaking out.

Why might March be better than May?

The NSW state election is due to be held on March 23.

Recent polling shows the Berejiklian Government may struggle to hold onto power.

The rifts within the federal Liberal Party were identified as one cause for the comprehensive defeat of the Liberals in last week's Victorian election.

Those within the NSW Liberal Party fear they could also be punished for the federal woes.

"You would understand … that there is a real concern in New South Wales Liberal circles that a very good, outstanding government led by Gladys Berejiklian is going to have its prospects of success diminished because of the brand damage to the Liberal Party caused by the leadership change in August," Mr Turnbull said.

It's thought that by giving voters a chance to vent their frustrations at the federal Liberals — the cause of this "brand damage" — they may be more likely to support the state Liberals at an election a few weeks later.

Why might May be better than March?

Scott Morrison announced the date for an early budget last week.

The budget is usually held in May, and this adjustment to the calendar indicated May was all but certain for the election.

Although Mr Morrison has not confirmed the date, figures in the Government have also suggested a May election is likely.

More polling suggests the federal Coalition Government is trailing the Labor Party and would be unlikely to win an election in the near future.

But not only would the Coalition lose power, a heavy swing of voters away from the Coalition would mean many of their MPs would lose their seats.

Pushing out the election as far as possible gives the Morrison Government a chance to win back some of these drifting voters.

The extra time before a May election would also give Mr Morrison a chance to develop and announce policies he wants.

Given he only came to power in August — two extra months are significant.

Sorry, this video has expired Cormann says Turnbull 'entitled to his own opinion'

Why is the previous plan relevant?

Mr Turnbull said he and Mr Morrison had planned to go to the polls in March before the change of leadership.

That timeline appears to have been abandoned.

Mr Turnbull's contribution suggests Mr Morrison's latest plan is putting his electoral prospects ahead of the NSW Liberals — even though it was the federal party room that has been the cause of much of the party's recent angst.

Finance Minister Mathias Cormann sought to underplay the significance of this alleged change of timetable today.

"The timetable always was that the election was due by the end of May," he said.

Why would Turnbull say this?

It's not clear, although his removal from the prime ministership in August clearly remains front of mind.

Mr Turnbull described it as a "destructive, mad, pointless" move on Monday morning.

But he was clear to reject allegations his intervention today was driven by vengeance.

As a Sydney-based former MP, he has friends in the NSW Liberal Party and he may want to support these in their re-election bid.

And then there's the issue of his legacy.

Mr Turnbull's contribution inserts into the public area a comparison between the current Government and his.

NSW Liberals appear to want a March election.

In his contribution today Mr Turnbull declared he — not Scott Morrison — would have delivered this outcome.