Delivering the Margaret Thatcher lecture at London's Guildhall, Tony Abbott has said Europe needs to secure its borders from the influx of refugees.
Quoting the Bible, Mr Abbott said the imperative to "love your neighbour as you love yourself" is at the heart of Western polity but "right now this wholesome instinct is leading much of Europe into catastrophic error".
"All countries that say anyone who gets here can stay here are now in peril," he said in his first speech since losing the prime ministership.
Mr Abbott laced his speech with praise for Mrs Thatcher, calling the former British prime minister "Mrs T" and saying she revived the "great" in Great Britain.
The recently deposed prime minister told the black tie gala banquet that Europe ran the risk of weakening itself through "misguided altruism" if borders were thrown open to all comers.
"Given the scale of the population movements that are starting to be seen. There are tens, perhaps hundreds of millions of people living in poverty and danger who might readily seek to enter a Western country, if the opportunity is there. And who could blame them?
"Yet no country or continent could open its borders to all comers without a fundamentally weakening itself. And this is the risk that the countries of Europe now run through misguided altruism."
'Australia's boat turnbacks successful'
Mr Abbott outlined the measures that his and John Howard's government put in place to stop boats bringing asylum seekers to Australia, including offshore processing, denial of permanent residency and turning boats back to Indonesia.
He said the boats had stopped, migrant detention centres had all but closed and there were no more deaths at sea.
"That's why stopping the boats and restoring border security is the only truly compassionate thing to do," he said to applause.
Mr Abbott said because people smuggling was a global problem and Australia was the only country to successfully defeat it, the Australian experience should be studied.
"The Australian experience proves that the only way to dissuade people seeking to come from a far is not to let them in," he said.
"It means denying entry at the border for people with no legal right to come, and it means establishing camps for people who currently have nowhere to go."
He advocated turning boats around in the Mediterranean, denying entry at borders and setting up camps for people who have nowhere to go.
He said it would "gnaw at our consciences - yet it is the only way to prevent a tide of humanity surging through Europe and quite possibly changing it forever."
'Special forces soldiers may be needed in Iraq, Syria to defeat IS'
Mr Abbott also warned that Western special forces soldiers may be needed on the ground in Iraq and Syria to defeat Islamic State jihadists.
He said that given the horrors unleashed by the Islamic State group in Iraq and Syria it was striking how little had been done to address the problem at its source.
Australia had joined US-led air strikes on IS but the jihadists could not be defeated without more effective local forces in a part of the world "that's such a witches' brew of danger and complexity".
"Everyone should recoil from an escalating air campaign, perhaps with Western special forces on the ground as well as trainers yet as Margaret Thatcher so clearly understood over the Falklands, those that won't use decisive force, where needed, end up being dictated to by those who will."
Abbott praised for 'heroic' speech
The leader of UK's anti-immigration party UKIP, Nigel Farage, welcomed the speech.
A long admirer of Tony Abbott's policy of turning back asylum seeker boats, Farage said the speech hit on all the right points.
"[It was] heroic and absolutely right," he told ABC Radio National.
"There is a very big difference between being a civilised country that recognises that there are genuine refugees in the world from time to time - and having a lunatic policy that I'm afraid Ms Merkel, the German chancellor, pushed, saying: 'please the world come here, we're pleased to have you.'
"And what we have seen, even from the EU's own figures is that over 80 per cent of people are economic migrants - they are not people who are qualified for refugee services still.
"And I think Tony Abbott is absolutely bang on."
He said Europe should be learning from Australia's policy of turning back asylum seeker boats.
"I think the policy that Abbott and Australia had with a similar problem with the boats coming. You are dealing with it correctly. Europe is dealing with it very badly.
While in London, Tony Abbott met with UKIP migration spokesman Steven Woolfe.
Backlash
But outside of the Tory audience, asylum seeker advocates and politicians were quick to criticise the message of the speech.
Demetrios Papademetriou, president of the Migration Policy Institute, said Abbott's plan for stopping Europe's migrant crisis is "completely unrealistic".
"The idea that Europe would behave like Australia it is a preposterous idea," he told ABC Radio National.
"It betrays a complete lack of what the European is and what the member states can and cannot do, both legally but also in terms, of what their populations expect them to do."
He dismissed the characterisation that asylum seekers fleeing the Middle East were economic migrants rather than refugees.
"This also a complete misunderstanding of what is happening in the European situation. There is no way that the European country would be willing to actually force people to stay in a particular country."
He said any legislative changes at an EU-level along the lines of what Tony Abbott is proposing would never eventuate.
'Change in legislation at the level of the European level is just about the most difficult thing to do because you are not going to have the agreement that is required in the European parliament, which is decidedly far more liberal than any of the parliaments of the member states.
"And the European Commission would fight this tooth and nail. We know for those things to happen you're going to have a complete upending of what that it is that Europe has set out to create."
Federal opposition leader Bill Shorten condemned the speech as inappropriate.
"I am not sure Tony Abbott on a victory lap giving a Margaret Thatcher lecture is exactly what Europe needs to solve its problems," he told reporters in Sydney.
"I don't think the European leaders need lectures from Malcolm Turnbull, Tony Abbott or Bill Shorten about what to do. I think the issues there are issues which the Europeans have to grapple with and simply saying Australia has all the answers is not the right way to go."
Australian Greens senator Sarah Hanson-Young said equating compassion for refugees with catastrophe is absurd.
- with AAP
