THERESA May’s Chequers Plan could create a £1 billion “post-Brexit bonanza for smugglers,” claims a pro-EU campaign today as consumers were warned that a no-deal scenario would push up food prices.

After Michel Barnier, the EU's chief negotiator, blew a hole in the Prime Minister's key customs proposal - the Facilitated Customs Arrangement - making clear the EU27 would not allow a non-EU member to collect its tariffs, the People’s Vote also picked fault with the UK's customs blueprint.

It claimed, given there would be no border checks, then smugglers would be free to transport goods in and out of Britain without controls on whether or not duties had been paid.

Consequently, the campaign said false claims about the final destinations of goods could enable smugglers to import into Britain without paying tariffs and then transfer those goods to the EU, thus evading duties that applied there.

“The Government is already in a total mess over its fantasy customs plans and this shows the serious consequences that the Brexit chaos has for our country,” declared Labour’s Wes Streeting, a leading supporter of The People’s Vote.

“The UK has a proud track record in tackling organised crime. For Brexit to make it easier for people to illicitly smuggle goods across our border and not pay their way is simply unacceptable,” insisted the London MP.

The backbencher added: “Nobody in Britain voted for the return to a golden age of smuggling. As new facts about Brexit come to light every day, it is clearer than ever that people need to be given a vote on the final deal.”

The People’s Vote calculated the £1bn Brexit bonanza figure by listing various goods and foodstuffs, which have varying EU tariffs, contrasting them with a zero-rated UK tariff, and then working out how much smugglers could potentially save.

For example, if EU tariffs were evaded: the £1bn EU import value of men’s and boys’ shirts from China would produce a £132m Brexit bonanza; £4.6bn of footwear also from China a £506m bonanza; £324m beef from Argentina a £41m bonanza and £1.8bn of coffee from Brazil a £109m bonanza. With other items, the campaign group calculated the total could be £1.07bn.

Meanwhile, Lord Price, the former International Trade Minister, warned that a no-deal Brexit would put up the cost of basic foodstuffs “pretty significantly”.

Mrs May told farmers and food producers at the Royal Welsh Show in Powys on Thursday that Brexit offered a "real opportunity" for Britain’s farming industry.

She and her senior colleagues have insisted the public should be comforted and reassured that the UK Government is taking “sensible” measures to stockpile food and medicines should Britain crash out of the EU without an agreement.

But Lord Price, a former managing director at Waitrose, made clear a no-deal Brexit would push up the cost of fruit and vegetables, meat and dairy products because they could not be stockpiled.

Noting how 80 per cent of vegetables consumer in the UK came from Europe, the Conservative peer, who left the Government in September, said: "What you will see is rather than a pinch on supply - although that is highly likely - is a pretty significant increase in the cost of fruit and veg, the cost of meat and the cost of dairy products."