Tony Abbott says Peter Dutton was reluctant to challenge Malcolm Turnbull for the leadership of the Liberal Party and believes the party now has a "pretty good" chance to win the next election.
Mr Abbott - who backed Mr Dutton's failed bid for the top job - said he was confident Australia was in "better shape" this week than before Scott Morrison took over as prime minister.
"He (Dutton) was a most reluctant challenger ... just as I was back in 2009," Mr Abbott said, in reference to his deposing of Mr Turnbull as leader.
In a speech in Sydney on Monday, Mr Abbott said Mr Morrison had strong character and expected him to install a "sharper difference" between the Liberal and Labor parties ahead of the next federal election.
"I am confident, given the ministerial appointments that he's made, that there will be better policy, there will be a united party, and there will be a sharper difference with our opponents," Mr Abbott told the Centre for Independent Studies.
"I think that our party will be far less toxic in the future than it has been in the recent past, and I think that that will be good for all of us."
Mr Abbott said the party was now more likely to win the next election with Mr Morrison at the helm.
That's despite the latest Newspoll taken just after Friday's leadership showdown showing the coalition's primary vote had slipped to 33 per cent, the worst result in a decade.
"I'm confident that we do now have a better-than fighting chance of winning the next election. I'm not saying we're favourites by any means but I think we now are competitive," he said.
"As long as you're in the race, you can always win."
Mr Abbott also cautioned his Liberal colleagues to refrain from sniping or undermining each other during internal disagreements.
"May I express my fond hope that in the weeks and months and years to come, political success will be determined again more by character and less by polling.
"The contest within parties should be conducted with honesty. If we disagree, let us do it openly and honestly.
"Let us never in the future say one thing to someone's face and something totally different behind their backs - that has been the poison in our polity."
In a wide-ranging talk, the former prime minister reiterated his calls for a cut to immigration and gave US President Donald Trump the tick of approval.
"While there hasn't been a lot of finesse about some of the things that he has done, I would say that on balance, he has more good than harm and that this is going to be a significant presidency in the way that not all presidencies are," he said.
