BREXIT-loving UK Government ministers, and their supporters, continue to fail spectacularly to make any serious case for there being anything other than economic damage from Brexit.

However, their enthusiasm for clutching at straws and celebrating seems as great as ever.

They would do well to reflect on the fact that the view in financial markets is that the Bank of England Monetary Policy Committee’s decision this week on whether or not to cut UK base rates from 0.75 per cent will be a knife-edge call.

And they should think about the reasons why a reduction in benchmark interest rates is being considered. The UK economy is, even in the context of its dismal record under the Conservatives since 2010, in grim shape indeed. It looks to have contracted or stagnated in the fourth quarter of last year – we will find out when official figures are published next month. Brexit-related uncertainty has been a big factor in this weakness, as it has been for years now, and that is before we even get to the exit door.

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The transition period will prevent a ­cliff-edge Brexit, after the UK’s departure from the European Union on Friday.

But you would surely expect worries among businesses and consumers to build again as a Boris Johnson Government hell-bent on a hard Brexit – leaving the single market and ending the free movement of people crucial to the economy and society – negotiates with our long-suffering EU neighbours.

Bank of England governor Mark Carney has been among those MPC members who have flagged the possibility of a near-term cut in interest rates.

In a speech earlier this month, he talked a lot about the impact of Brexit and declared: “There are downside risks from global growth and the possibility that uncertainties over future trading relationships could remain entrenched. With the relatively limited space to cut Bank Rate, if evidence builds that the weakness in activity could persist, risk management considerations would favour a relatively prompt response.”

This is the kind of serious stuff on which the Brexiters should focus.

It was interesting, in this context, to observe Brexit Secretary Steve Barclay last week enthuse about the potential for British wine.

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It has surely been a long, hard slog for British (mainly English, given climate factors) wine, and it would be difficult to imagine personally ever even thinking of picking this over an offering from one of our sunny mainland European neighbours steeped in wine-making tradition. Each to their own, however. Wine is thankfully generally a far less divisive issue than Brexit. And fans of English wine are obviously as entitled to their preference as anyone else.

However, Mr Barclay seems to envisage something much, much greater than a niche following for English wine. Like patriotic buying of British-made cars.

He tweeted: “Over 99% of wine consumed in the UK is imported. After we leave the EU on 31st Jan we have a prime opportunity to help this vital sector thrive.”

Former Financial Times editor Lionel Barber’s comment, as he retweeted Mr Barclay, just about summed things up: “I’m forever blowing bubbles, pretty bubbles in the air, they fly so high, nearly reach the sky, then like my dreams they fade and die…..#ChampagneBrexit.”

The original tweet from Mr Barclay, while it is laudable he wants to support UK wine, is remarkable in terms of its language, with “prime opportunity” and “vital sector” surely overdoing it a bit.

However, it is typical of the Brexiters’ desire to cling on to what they seem to actually believe at times might be meaningful benefits of leaving the EU.

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The promise of big new trade deals seems to have disappeared like snow off a dyke.

And what we are left with is the fizz of the Brexiters’ enthusiasm. This exuberance will be irritatingly to the fore this Friday, as the Leavers celebrate their Pyrrhic victory with parties, likely unbowed by their failure to get Big Ben bonging.

The nine-strong MPC will, the day before, be making a far more sober assessment. It will have to contemplate the UK’s economic weakness, and the actual, real implications of Brexit, and decide whether or not it needs to act this week to prepare for what is to come by cutting a UK base rate that is only a half-point off its all-time low.