John Howard has dismissed the doubters, offering Malcolm Turnbull some reassuring words as he marks a year since toppling Tony Abbott for the nation's top job.
Mr Howard says Mr Turnbull, who will clock up his first anniversary as PM on Wednesday, can survive a three-year term of government as long as he believes he can.
But the former prime minister says Mr Turnbull must unite the Liberal Party behind him, and have a clear economic and political program and the respect of the broad church of the party.
"There is no reason why Malcolm Turnbull shouldn't lead the government right through to the next election and do it successfully," he told Sky News on Sunday.
Unsurprisingly, Opposition Leader Bill Shorten believes Mr Turnbull has turned out to be a "great national disappointment" in a year of "dithering and disunity".
He said Mr Turnbull characterising his first year as "so far, so good" will leave people scratching their heads to think of a single achievement of his government.
"Malcolm Turnbull is not the prime minister he promised he would be," Mr Shorten told AAP.
"He can't go a week without stuffing something up ... no wonder Tony Abbott is trying to take the job back off him."
Deputy Prime Minister Barnaby Joyce listed the national broadband network, economic growth of 3.3 per cent and continued strong borders among the Turnbull government's achievements.
"He won the last election, that's a pretty good start," Mr Joyce told ABC TV.
He said the government is on a path to return the budget to a position where today's kids and grandkids have the same form of education and health system, and defence protection, as their parents.
"If we can't turn the budget around because the Labor Party keeps blocking issues, then we won't be able to provide that to people in the future," he said.
Mr Howard, who enjoyed nearly 12 years as prime minister, says Mr Turnbull must lead a government willing to reform the tax system and industrial relations.
"You can't avoid that ... the fact they are difficult doesn't mean you don't try them," Mr Howard said.
But Mr Turnbull said both these issues were either in the budget or taken to the election.
He said these included the largest reforms to superannuation and business tax cuts in some 15 years.
At the same time, the trigger for the double dissolution election were two important industrial relations legislation - the reinstatement of the Australian Building and Construction Commission and the registered organisations bill.
"So tax and IR are very much on the agenda," Mr Turnbull told reporters in Canberra.
Mr Howard also admitted he's the "odd man out" when it comes to the topical issue of political donations, saying unlike many on both sides of the political divide, he isn't against foreign, corporate or union donations.
"I think the one big change that is needed is more timely disclosure of donations, transparency is the key," Mr Howard said.
He believes the whole political class is panicked on this issue and is acting as if federal politics is so potentially corrupt it has to insulate itself against undue financial influence.
"In all the years I was in federal politics, I did not see any significant evidence of corruption," he said.
