SIR - The excellent William Keegan, doyen of economic commentators, writes that whereas Brexiters claimed that leaving the EU would free up £350 million per week for the NHS, actually the disruption caused by Brexit is costing the UK four per cent of its national income every year.

The £350 million figure, posted on the side of that bus, was strongly disputed the UK national statistics authority. Any “saving” would be very much less. And in any case it has never arrived nor been passed on to the NHS.

The four per cent loss figure has been substantiated by at least two independent authorities. Since Brexit, it has cost the country £80 billion a year. If the £350 million pw figure had materialised by now it would have grossed up to £18 billion a year.

So, to get hold of an £18 billion that has proved totally illusory Brexiters have cost us £80 billion. As an exercise in self-harm Brexit has been hugely successful.

As Sir Ivan Rogers, for many years the UK ambassador to the EU, previously commented, by pursuing Brexit we have been “exchanging a three course meal for a bag of crisps”.

John Cole, Oakroyd Terrace, Baildon