04/10/2017 3:26 PM AEDT | Updated 05/10/2017 11:20 AM AEDT

Bob Hawke Just Let Fly On The Same Sex Marriage Postal Survey

And he put it all on Prime Minister Malcolm Turnbull.

Andrew Meares/Fairfax
Former Prime Minister Bob Hawke called the $122 million postal survey the

CANBERRA -- Bob Hawke is from the "other side" of politics, so criticism of Prime Minister Malcolm Turnbull could be expected, but he really pulled out all stops on Wednesday describing the Turnbull Government's $122 million postal survey on same-sex marriage the "worst economic decision made by any Prime Minister since federation".

The former Labor Prime Minister made the blistering assessment of the voluntary, non-binding poll while helping to launch the book Incorrigible Optimist by former Foreign Minister Gareth Evans at the National Press Club in Canberra.

Hawke had made his presentation about Evans and was sitting in the audience, when Evans was asked by a journalist about the Turnbull Government's controversial postal effort to change the Australian Marriage Act to legalise same-sex marriages.

When Evans finished, the former PM offered his own point, describing the survey decision as "the worst economic decision made by any Prime Minister since federation".

Andrew Meares/Fairfax
Former Prime Minister Bob Hawke launched the biography of Hawke era minister Gareth Evans.

"It cannot produce a decision. It still requires a vote of the Parliament, whatever the result of the vote is."

"It costs $122 million bloody dollars."

Turnbull, a personal and public supporter of same-sex marriage and for holding a free vote on parliament on the issue, now has a rock solid position for supporting a public vote as fulfilling an election promise and letting the "people have a say".

Conservatives in the Liberal Party and Nationals have been thwarting attempts to hold a free vote, but Hawke indicated that was no excuse for Turnbull's actions.

"Can you imagine a Prime Minister would make a decision in these stringent times?" he posed. "Spending $122 million on a process that can't produce the result when you could do so much to reduce the gaps (in what) Aboriginal people (face), education and so on?

"Without any question the worst economic decision made by any Australian Prime Minister."

Evans also had a few words for the decision to hold the postal survey, saying Turnbull had "sold himself completely" to the "trogs" (troglodytes) in Liberal Party.

"I find it difficult to be anything but appalled by the quality of the policy-making regime we are seeing from the present government," the now ANU Chancellor said.

On Wednesday afternoon, former Prime Minister Tony Abbott used his weekly slot on Ben Fordham's 2GB radio show to hit back at Hawke's claims, saying he believes the former Labor leader to be "suffering from memory loss."

"Let's face it, it was the former Gillard-Labor government which spent $16 billion on school halls, grotesquely overpriced school halls, including on schools that already had them," he said.

"It was the former Rudd-Gillard government that spent $2 billion putting pink batts into roofs which caught fire and then it had to spend $2 billion getting them out.

"I have a lot of respect for Bob Hawke as Prime Minister, he was a good Prime Minister by Labor's standards, but some years ago he called a pensioner who gave him a hard time at a shopping centre -- I think the phrase he used was 'a silly old bugger,' -- and I think it's time Bob looks in the mirror, frankly."

The postal survey has been widely criticised as divisive, damaging, non-binding and voluntary, although the Turnbull Government has promised that a "yes" result will lead to a vote in federal parliament on a private member's bill by the end of the year.

The Australian Bureau of Statistics on Tuesday estimated it had received 9.2 million (57.5 per cent) of the 16 million survey forms.

On Wednesday, Turnbull told the ABC's AM program that the turnout was a "great outcome".

"What that tells you is that Australians wanted to have their say.

"So I think it is a ringing endorsement of the government's decision to give every Australian their say on this issue."