Business Secretary Kwarsi Kwarteng has said it is “absolutely right” the government is ready to tear up parts of post-Brexit trading arrangements in Northern Ireland.
The cabinet minister also accused Brussels of being “unreasonable” in its approach towards the Northern Ireland Protocol.
But Ireland’s foreign minister Simon Coveney said his country was also “frustrated” dealing with the fallout of Brexit, which he said had cost it hundreds of millions of euros and threatened the peace process.
Pressed on Sky News’s Sophy Ridge On Sunday programme if the UK administration was prepared to ditch parts of the agreement, Mr Kwarteng said: “Absolutely right.”
He added: “We have had a number of people in this country whose presumption has been that the government is always wrong and and the EU is always right.
“That’s clearly too simplistic. We have tried to negotiate.
“The protocol itself says it can be abrogated unilaterally if it’s shown not to be working.
“And clearly, if political stability is our number one priority, and people are saying that they won’t go into power sharing if it isn’t changed, we have to consider very carefully how we can change it.
“Article 16 is part of the protocol itself, and… it says quite clearly that there’s a scope to change it unilaterally.
“Unilaterally means that we can do that ourselves without having to reach agreement with the EU.”
Mr Kwarteng added: “I think the EU are unreasonable, frankly.
“They won’t show much flexibility and that’s why we are in the position we are in.
“The protocol isn’t working and we have to be prepared to invoke Article 16.”
He also played down the prospect of a trade war if the UK carried out its threat.
EU leaders have warned of retaliatory measures if the UK invokes Article 16 of the protocol to unilaterally suspend some of the arrangements, including the requirement for checks on goods crossing from Great Britain to Northern Ireland.
Mr Kwarteng said it would take “a very long time” for any new EU tariffs to be approved and that it was important the UK was prepared to act unilaterally to maintain political stability in Northern Ireland.
“Political stability in Northern Ireland is our number one priority. We should be able to act in a sovereign way. Northern Ireland is as much of the United Kingdom as England, Cornwall, the South east, and we are responsible for that.
“Any tariff situation would have to go to arbitrators. It is not something they can do willy nilly, arbitrarily.
Referring to Article 16, he said: “It does allow people to act unilaterally and we have got ultimately to be prepared to invoke it.
“I don’t think they are necessarily going to be able to slap on tariffs arbitrarily.
“I think it will take a very long time for that process to work out.
“As far as I am concerned, we have absolutely the right to invoke Article 16 and reopen or re-examine the protocol.”
But Irish foreign minister Simon Coveney told Ridge: “The EU wants to continue to negotiate, wants to show flexibility, wants to compromise.”
He added: “Ireland is also frustrated. We are dealing with the consequences now of a decision by the British people on our own country that has cost us hundreds of millions of euros, that is risking the peace process and its institutions on the island of Ireland.
“When we focus on frustrations we need to think beyond Westminster.”