With the fraught negotiations over Brexit continuing to embroil British politics, the nation's former prime minister, David Cameron, says his "greatest regret" is that those who advocated to stay in the EU lost the vote — which ultimately divided the country, paralyzed the government and left Britain increasingly at risk of leaving the European Union without any deal.

After resigning in 2016 in the wake of Britain's vote to leave the EU, Cameron has broken his silence on his role in unleashing the ongoing political drama around Brexit. He writes about it in the new book For the Record.

In an interview with NPR's All Things Considered, Cameron laments his call for the Brexit referendum — a vote that shocked Britain and the whole of Europe when 52% of voters chose to leave the EU.

"The greatest regret is that we lost the referendum, that I didn't prevail, that we could've fought perhaps a better campaign, we could have conducted perhaps a better negotiation — perhaps the timing wasn't right — and that I didn't take the country with me on what I thought was a really important issue," Cameron said.

Even though he opposed Brexit, the former Conservative Party leader said he underestimated the extent to which voters understood the stakes of the referendum.

"I think the biggest mistake was letting expectations about what a renegotiation of Britain's position in the European Union could achieve," he said. "I allowed people to think there were much more fundamental changes — that we could almost have a sort of pick-and-choose aspect to which European laws we obeyed and which we didn't. And this, I think, was damaging."

In the three years since his resignation, Cameron has come under fire from critics who say he recklessly called for a referendum in an effort to appease more conservative elements of his party, and then stepped aside when he lost the vote. Cameron said he resigned because he felt he could not carry out negotiations in good faith for a cause he did not himself support.

"I was wholly on one side of the argument and so I felt it was right to resign, having lost because the country needed a new prime minister with the credibility to take us forward and deliver the outcome of the referendum."

"But of course, you know, I will, to my dying day, wonder whether there was something more we could have done to secure what I thought was the right outcome — which was to keep Britain in."

The man now charged with finding a solution for Brexit, Prime Minister Boris Johnson, has vowed to leave the EU even if Britain is unable to forge a deal with Brussels — a scenario that economists warn would be devastating for the country's economy. But Johnson was rebuffed in that effort last week when Britain's Supreme Court ruled that his effort to suspend Parliament with just weeks remaining until the country's scheduled departure from the EU on Oct. 31 was illegal.

The ongoing political drama has left Britain deeply divided between the "Remainers" and the "Leavers."

"I think what Boris is doing right is he's trying to get a deal from Brussels. He wants to take that deal back to Parliament and he wants to deliver the outcome of the referendum. In doing that, he's got my support," Cameron said. "I think what would be a mistake is trying to leave without a deal because I think that would lead to a lot of economic dislocation and would be damaging."

Asked about whether he has a responsibility to help mend political divisions in the country, Cameron said he does not see a role for himself.

"As the person who called the referendum and lost the campaign, I'm not sure that I should be active in current politics. But I am deeply depressed by what's happening."

Cameron still said he believes Britain would "be better off inside" the European Union, but understands what led voters to support leaving.

"It's not an illegitimate choice for the sixth biggest country in the world to say to the European Union, we want to be your friends, we want to be your neighbors, we want to be your partners," he said. "But we don't want to be members, and that's the choice that we've taken. And I don't think that is an illegitimate choice or an impossible choice to deliver."

NPR's Elizabeth Baker and Tinbete Ermyas produced and edited this story for radio. contributed to this story

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