As the trade and industry secretary who implemented the original single market programme, I trumpeted its potential benefits.

Indeed, the initial idea was sensible. It involved mutual recognition of each member’s product standards after removing any anti-competitive features. If it had remained like that I would support us continuing to follow single market rules.

Unfortunately, the single market changed from mutual recognition to centralised, uniform and burdensome regulation.

This helped established firms consolidate their grip on the market by making it harder for newcomers to enter.

So us remaining subject to single market rules, especially new rules they may impose on emerging new technologies where Britain is ahead of Europe - as proposed at Chequers – would be an act of grievous self-harm.

Ministers, of course, rightly want to minimise customs procedures on trade with the EU while regaining the ability to do free trade deals with the rest of the world. That’s why officials initially proposed a “customs partnership”.

It would have required us to levy EU tariffs on all imports entering the UK from outside the EU. Importers would then have had to claim a rebate if the UK tariff was lower than the EU’s and they could prove the item remained in the UK.

The cabinet rejected this as hugely bureaucratic and because it made free trade deals impossible. No country would remove their tariffs on our goods if we still levied EU tariffs on theirs.

So at Chequers a new proposal was unveiled - the Facilitated Customs Arrangement (FCA) - which claimed to overcome this problem. Sadly this claim was based on a gross statistical deceit.

Under this plan, British customs officials would collect British tariffs on goods clearly destined to remain in Britain and EU tariffs on goods they knew would end up in the EU.

Together these were claimed to account for “up to 96 per cent of UK goods trade”. Again, if importers could show their goods remained in the UK, they could reclaim the tariff differential.

But ministers at Chequers were reassured that as only 4 per cent of trade would be subject to this cumbersome repayment mechanism it would not put off our prospective free trade partners.

It has since emerged that in fact 16 per cent of all our goods imports from outside the EU and over 40 per cent of imports which might benefit from free trade deals, would face this bureaucratic hassle.

No country would enter a free trade deal with us on this basis. The FCA makes a mockery of us having an independent trade and regulatory policy. Had ministers known this, Chequers probably wouldn’t be Government policy.

The Treasury reduced their figure by including imports from the EU, for which the scheme is irrelevant, and - irrelevant to the point of absurdity - all UK exports both to the EU and the rest of the world.

For this statistical duplicity, heads should roll. We cannot tolerate our Brexit deal being negotiated on the basis of such grotesquely misleading figures.

Instead of engaging in such a serious misrepresentation and trying to delude the British people with a Brexit that is essentially a mystical re-branding of the single market and a cosmetic repackaging of the status quo, we need to focus on an honest, conventional, Canada-style free trade deal.

Lord Lilley is a former trade secretary