Every so often, one single number can change an entire political conversation. So here, dear reader, is my candidate for this weekend’s game-changing fact, which reveals why it is desperately important that Brexit be used to negotiate a much better deal for British shoppers.

On average, prices paid by EU consumers are 6pc higher than the prevailing world price; in many cases, prices are much higher than average, with EU consumers paying 31pc more for beef and veal, for example; two hugely important products.

It’s the real and entirely unacceptable cost of living in the EU; a far greater problem than the membership fee that richer countries must pay to Brussels

The reason for such rip-off prices? Europe’s protectionism, though lack of competition doesn’t help either (and is related to barriers to trade with the rest of the world). As ever, it is the poor who are hit the hardest: they spend a higher share of their income on essential products such as food.

The figures, from the OECD, were unearthed by Andrew Tyrie, the Tory MP, who has just written an interesting report on Brexit published by Open Europe. I disagree with some of Tyrie’s broader arguments, but his paper is well worth reading.

My point is this: there are, of course, costs as well as benefits to Brexit. The Government’s great, historic task is to maximise the upside while minimising the downsides. To deliver the best possible solution, it will be key to tackle the absurdity of consumers having to pay such elevated prices, and push through policies that bring these down to global, free-market levels as soon as possible.

A 6pc drop in prices would represent an immense gain in welfare terms: it is one of the great pots of gold at the end of the Brexit rainbow, with the added benefit of truly existing. There are many other gains to be had, but lower prices are the most immediately tangible benefit.

David Fuller's view

I agree, and the benefits of Brexit should not be postponed by years of tortuous negotiations.  The best course, in my opinion, is to invoke Article 50, leave with minimal or even no negotiations, and very closely thereafter, simply declare unilateral free-trade.  The UK would save a considerable amount of money and hassle by doing this.  Thereafter, using our membership of the World Trade Organisation, we would find Germany and many other EU countries all too happy to recommence trade agreements with Britain.  

Here is a PDF of Allister Heath's article.