A VOTE to leave the European Union would plunge Britain back into recession, Alistair Darling, the former Labour chancellor has warned, as a poll gave the Remain campaign a record 18-point lead.

The Labour peer, in a speech to the CBI’s annual dinner in London, said when economic experts from the IMF’s Christine Lagarde to the Bank of England Governor Mark Carney warned of recession on the back of Brexit, then people should “sit up and take notice of the scale of the risk we face”.

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He told business leaders: "Recent experience and historic evidence shows that when our economy suffers this kind of serious damage, insolvencies, repossessions and unemployment, particularly among young people, all soar.

"Economic insecurity of the type being forecast would be disastrous for working people's life chances and living standards,” declared Lord Darling of Roulanish.

But at the dinner, Lord Howard, the former Conservative leader backing Brexit, claimed a lack of democracy in the EU was hurting business.

"If we Vote Leave, we can take back the power to make our own trade agreements. At the moment, we have no trade deals with India, China, Brazil or even Australia and New Zealand. We have to wait for 27 other member states to agree before we can arrange a single trade deal,” he argued.

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The Tory peer said if Britain left the EU with no trade deal, which was inconceivable given the tariff free zone from Iceland to Turkey, UK exports would face EU tariffs averaging just 2.4 per cent.

"But,” he pointed out, “our net contribution to the EU budget is equivalent to a 7.0 per cent tariff. Paying 7.0 per cent to avoid 2.4 per cent is mis-selling on a scale that dwarfs the scandal of PPI."

Meantime, an Ipsos Mori telephone poll of 1,000 British adults gave a boost to the Remain campaign. The snapshot for the London Evening Standard put Remain on 55 points against 37 for Leave. The 18-point advantage for Remain is the largest since the referendum was called for June 23.

Earlier, leading Brexiteer Boris Johnson dismissed criticism of his comparison between Adolf Hitler and the EU as "synthetic outrage" after Conservative grandee Lord Heseltine suggested it had damaged his chances of ever leading the party.

In a withering attack, the Tory peer, a former deputy prime minister, described the former London mayor’s comments as reckless and irresponsible, while Mr Johnson's fellow Leave campaigner Chris Grayling, the Commons Leader, repeatedly declined to endorse them in a radio interview, describing the remarks simply as “a historian's comment".

Asked about Lord Heseltine's broadside against him, Mr Johnson told TV cameras outside his London home: "The most important thing is that everybody should cut out the synthetic outrage about things I haven't said and stick to the facts.

"The facts are that the EU is now producing about 60 per cent of the law made in this country; it's changed out of all recognition from what we signed up to in 1972, it is making it impossible for us to control our borders and it costs about £350 million per week. The only safe option is to vote Leave on June 23."

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Leading Outer Iain Duncan Smith dismissed Lord Heseltine as a "voice from the past" while his anti-EU colleague Jacob Rees-Mogg added: "Lord Heseltine is a frightful old humbug, who divided the Conservative Party more than anybody else in our modern history and a period of silence on his part would be welcome."