IT was Boris Johnson, who last year remarked that he was all for “having our cake and eating it,” adding: “We are pro-secco but by no means anti-pasto.”

A few weeks later Chancellor Philip Hammond could not resist a dig at his Brexit chum, declaring how the UK Government was realistic that leaving the Brussels club would indeed have its consequences, noting: “We can’t cherry-pick; we can’t have our cake and eat it.”

For some, however, having your cake and eating it is what politics is all about; why have cake, if you can’t consume it?

But the charge is that the Brexiteers are living, as Government critics were quick to point out with the release of the proposals for interim customs arrangements, in la-la land.

Having unveiled its long-awaited paper on future customs arrangements, the UK Government has, it seems, not yet decided on its preferred option, offering up two alternatives.

One would mirror the EU customs union so there would be no customs checks at all; a unique and untested option. The other would use technology to produce a highly streamlined system; but with no clue as to costs or timings.

Plus, if it all were to go pear-shaped and there was no deal, the UK Government notes how it would have to slap duty and VAT on goods from the EU, pushing up the costs to British consumers.

Amid the political flak, the UK Government’s proposal on having an interim period was welcomed as sensible by British business leaders as it would help smooth the transition from being in the customs union to being outside it.

But they seemed to be forgetting one not-so-small point; the politics of Brexit.

The interim proposal for an undisclosed period of time would effectively mean the departing UK would have all the benefits of being in the customs union while not having to abide by its core principle; of not being able to negotiate separate trade deals.

Guy Verhofstadt, the European Parliament’s chief negotiator, has described the UK Government’s hokey-cokey proposal on customs arrangements as “fantasy” while Karel de Gucht, the former EU trade commissioner, pointed out it would mean Britain using the proposed interim period to negotiate trade deals to “undercut” the EU with “preferential tariffs” for other nations.

It is one thing to have your cake and eat it but it would add insult to injury for Brussels to expect Jean-Claude Juncker to bake it and Donald Tusk to serve it up too.