Malcolm Turnbull has described former prime ministers Tony Abbott and Kevin Rudd as “miserable ghosts” while delivering a brutal assessment of the federal government.

Speaking to young leaders in New York on Friday, Mr Turnbull slammed the government over the “crazy” Liberal leadership crisis that led to his eviction in August and hit out at his predecessors.

Mr Turnbull pointed out he was behind 51 to 49 per cent in the published polls but was actually ahead by four points in internal tracking polls across 40 marginal seats.

“But for reasons that they’ve not been able to explain, you know, there was an element of the party and of the media that wanted to blow the government up, and they did,” he said in a recording of his remarks obtained by Nine News.

“And of course, they didn’t get their guy up. They got ScoMo (Scott Morrison).”

In reference to the behaviour of former prime ministers Tony Abbott and Kevin Rudd, Mr Turnbull said it was important not to be driven by hate.

“When you stop being prime minister, that’s it,” he said.

“There is no way I’d be hanging around like an embittered Kevin Rudd or Tony Abbott. Seriously, these people are like, sort of miserable, miserable ghosts.”

Speaking before the recording was aired, Treasurer Josh Frydenberg said he sympathised with his former boss.

“It’s a pretty challenging situation to be prime minister one day and not the next,” he told Nine.

“But what we have seen, through the strong economic numbers that the government has released, is that he can take a lot of credit for that.”

The treasurer said he stuck by Mr Turnbull right through the Liberal leadership crisis.

“But the party room spoke. We are getting on with it and Scott Morrison has made a fantastically strong start,” Mr Frydenberg said.

Appearing on the ABC Insiders program on Sunday, Mr Morrison said he was confident the government would have won the next election under Mr Turnbull.

Mr Morrison deflected all blame for the leadership insurrection to Liberal MPs who voted for it.

“As John Howard always said, the leadership of the parliamentary Liberal Party is the gift of the parliamentary party and you respect their decisions and you get on with your job,” he said.

-AAP