NIAC chair says constitutional issues around the Irish Sea border are an issue for the EU - not Stormont politicians

Speaking on the BBC’s The View programme, Mr Buckland urged unionists to focus on what was “achievable”.

He told Mark Carruthers: “I think focusing on what is achievable and what is within their direct control would be the best way forward” – implying that unionists are wasting their time trying to remove the Irish Sea border.

He said politicians should focus on bread and butter issues such as health and education “rather than constitutional issues that we all know are the province of either negotiators from the UK government – or indeed in the case of the Protocol – the EU”.

Baroness Kate Hoey said that while she appreciated that Sir Robert is new to his NIAC role – and she understands he is keen “to make a name for himself” – his comments are “shocking”.

The peer said: "I can’t believe that he is suggesting that the constitutional position of Northern Ireland is only alterable by the European Union. This goes even further than the EU having a say over our trading arrangements and it’s quite shocking that a chair of a NI select committee should be so much in hock to the EU”.

The Tory MP also told the BBC’s Mark Carruthers that “the time has come for intellectual, cerebral unionism. Muscular unionism will only take you so far”.

TUV leader Jim Allister has written to Sir Robert saying: “I found your remarks on ‘BBC The View’ that it was time for intelligent and cerebral unionism supremely arrogant and offensive.

“It is thinking unionists who repudiate the Protocol and refuse to give it the credibility of implementing it, because of its insidious assault on the very essence of unionism, namely the right to equal citizenship within our own country.

“With the Protocol requiring, through application of the EU Customs Code to NI, GB to be regarded as a third/foreign country whose goods must be checked coming into what is now treated as EU territory, where the EU, not British, writ runs in terms of the manufacturing and sale of our goods, its dismantling of the union is obvious. Little wonder the Supreme Court had to hold that it has put that key constitutional building block of our union, Art 6 of the Act(s) of Union, into suspension.

“Yet, it is in these circumstances that you wish unionists to operate this Union-dismantling Protocol through Stormont, with the added consequence of building its intended economic all-Ireland. Only the unthinking and those indifferent to the Union could do so. Refusing to implement our own destruction in common parlance is a ‘no brainer’.

“It was also disappointing to hear you at one and the same time boasting of your unionist credentials and then threatening the meddling of a foreign jurisdiction in the administration of this part of the United Kingdom. Surely, your unionism should make you a staunch opponent of such?

“I trust you might reflect on your advocacy of that which is consciously pushing Northern Ireland out of our union”.