The former Prime Minister, who quit after losing the Brexit referendum, appeared to have accepted the failures in his remain campaign, urging his audience against burying their heads in the sand.
During the launch of the new Coalition For Global Prosperity campaign – a group of military, political, business and faith leaders fighting to maintain Britain’s spending commitments on foreign aid – he said a “positive approach” is needed to engage with the surge of global populism.
Speaking to an audience of former cabinet ministers, senior MPs and charity officials last night, he said: “It’s no good I think in response to the wave of populism we’ve seen around the world, it’s no good to just push away these arguments and not engage with them.
“It’s no good saying to people — “you’re wrong to be concerned about high levels of immigration, just get used to it and understand what a benefit it is.
“People want immigration control and expect governments to deliver on it.
“It’s no good saying to people— ‘well you’ve just got to understand the beauties and wonders of free market economics,’ when people are very clear the economy is not working for everybody.
“We deal with it through programs like the government has done — minimum wages, better training, more apprenticeships. You have to take on the causes of this populism and deal with these arguments, not wave them away.”
Mr Cameron has avoided the spotlight since Prime Minister Theresa May was voted in as Tory leader and he gave a famous speech on the steps of Downing Street as he left office prematurely.
At the time, Mr Cameron admitted that he had got some decisions “wrong” during his days in office.
The former Tory leader, whose memoirs are expected to be published by HarperCollins next year, jokingly told the crowd he had used his time away from the spotlight to mull over his time in office, while he completes his book at his home in Oxfordshire.
Mr Cameron said: “Two years give you time to reflect — obviously from my shed, as you may have heard — about the things you got wrong, and the things that you got right.
“The decision to deliver 0.7 percent of our gross national income in aid is one of the things that I am proudest of. The most important thing was the act of political will to make this choice.
“We shouldn’t underestimate the controversy, or the difficulty, or the unpopularity, to be frank, among some people.”
Among those present were former Home Secretary Amber Rudd, former Conservative leader Michael Howard and Hilary Benn, backbench Labour MP and chair of the Brexit Committee.
Mr Cameron, who is being paid £800,000 for the book deal and said he was in “no rush’ to complete the book, told Express.co.uk in May he had completed 35 chapters and is merely being careful not to “rush” to the finish.
Many of Cameron’s recollections for the delayed-book are based on an audio diary he kept while at Number 10.
The audio includes 53 hours of recorded conversations with his friend Daniel Finkelstein, 55, who was also made a Tory peer in 2013.