Northern Ireland Protocol: Sammy Wilson says 'we have already identified a whole range' of government claims about deal which are wrong - such as the 'Stormont brake'

Mr Wilson also added that he had suspected the government’s request to involve King Charles in recent days was an indication that the deal was a bad one, in need of a positive gloss.

Sammy Wilson declined to say whether that would take days or weeks to reach a verdict though, telling Times Radio: “As long as it takes us to, first of all, look at the substance of the deal rather than the spin which the Government has given.

“We’ll be going back to the Government. We’ve already identified a whole range of things that the Government has claimed will happen, which we now know won’t happen because we’ve looked at the EU’s explanation of it."

He cited the example of the Stormont brake, saying: “The Stormont brake is not really a brake at all. It’s a delaying mechanism.”

He said the UK Government would have the final say over whether to veto a law, which it would be reluctant to do due to being “fearful of the consequences of trade for the rest of the United Kingdom”.

“The price of that would be that the EU would take retaliatory action,” he said, adding that he suspects the Stormont brake would therefore be “fairly ineffective”.

He added: “As members of the United Kingdom and in a democracy, we should have a say as to whether or not we are hived off and become a colony of the EU.

“It’s not the duty of the UK Government to safeguard the single market of the EU at the expense of the integrity and the unity of its own country. But that’s what’s happening at present.”

As to the involvement of the King in Monday’s finalising of the Windsor Framework, Mr Wilson said: “I think first of all it’s really an indication the Government knew this deal was not a great deal and were trying to persuade unionists to accept it on the basis that we have great respect for the monarchy.

“To use the monarch in the way in which he has been used, I think, is a very, very dangerous thing.”

The DUP will “decide how we convey our concern about that”, he added.