Former British prime minister David Cameron has said a second Brexit referendum cannot be ruled out, and accused Boris Johnson and Michael Gove of effectively "trashing" the British government during the 2016 referendum campaign.

In an interview with the Times newspaper, Mr Cameron admitted that he thinks about the consequences of the vote to leave the European Union "every single day" and worries "desperately" about what will happen next.

Mr Cameron said he thought another referendum could not be ruled out "because we're stuck".

"I'm not saying one will happen or should happen. I'm just saying that you can't rule things out right now because you've got to find some way of unblocking the blockage," he said.

In a memoir due to be released next week, Mr Cameron reportedly refers to his former Cabinet colleague Mr Gove as "mendacious" and said he and Mr Johnson behaved "appallingly" in the referendum campaign.

He said: "I say in the book: Boris had never argued for leaving the EU, right?

"Michael was a very strong Eurosceptic, but someone whom I'd known as this liberal, compassionate, rational Conservative ended up making arguments about Turkey (joining) and being swamped and what have you.

"They were trashing the government of which they were a part, effectively."

Mr Cameron, who said the Leave campaigners "left the truth at home" regarding Turkey joining the EU and the claim Britain sends £350 million a week to the EU, also criticised Home Secretary Priti Patel's "attack that wealthy people didn't understand the problems of immigration".

"It felt very like she was put on point to do some attacking of the government and its record. I suppose some people would say all is fair in love and war and political campaigns. I thought there were places Conservatives wouldn't go against each other. And they did."

The former PM - who admitted to being "hugely depressed" about leaving Number 10 - said Mr Johnson was "easy to work with" but admitted there had been "issues" between the pair.

On Mr Johnson's recent decision to prorogue Parliament for five weeks and withdraw the whip from 21 Tory MPs - including the likes of Ken Clarke and Sir Nicholas Soames - Mr Cameron expressed his disapproval.

"Taking the whip from hard-working Conservative MPs and sharp practices using prorogation of Parliament have rebounded. I didn't support either of those things. Neither do I think a no-deal Brexit is a good idea," he said.