All unionist politicians should distrust the ever jovial prime minister

Mr Johnson was emphatic that he could. He then tried to be humorous about it all, and said: “If somebody asks you to do that, tell them to ring up the prime minister and I will direct them to throw that form in the bin.”

The questioner, an NI Tory and healthcare exporter, had the sense to wonder afterwards whether to believe the PM or assume he is “just being bombastic and being Boris”.

It is a regrettable state of affairs that all unionist politicians should operate on the basis of complete distrust towards such commitments from Mr Johnson.

Not only has his previous outspoken support for the integrity of the UK shown to be almost worthless, his assessment was previously contradicted by his own Brexit Secretary Stephen Barclay, then again yesterday by Raoul Ruparel, a former special advisor on Europe, who said that “as things stand there will need to be exit declarations”.

The UK he said would need to negotiate this away.

Once again therefore, we are dependent on a UK government having to ask the EU to reopen a bad deal it has made.

It is a shameful state of affairs, yet the prime minister had the brass neck to turn up in Belfast on Thursday and behave in his usual, un-prime ministerial jovial manner.