Taoiseach Micheál Martin has said it is not inevitable that the UK government will trigger Article 16 of the Northern Ireland Protocol.
He urged Britain to consider the damage such a move would cause to its relationships with the EU and Ireland.
Minister for Foreign Affairs Simon Coveney warned at the weekend that if the UK moves to suspend elements of the protocol, the EU could do likewise with the Brexit trade deal.
Mr Martin has sought to play down talk of a looming trade war and urged the UK government to engage faithfully in negotiations.
The Taoiseach said: “I don’t think anything should be taken as inevitable in respect of the current talks on the protocol that are under way between the European Union and the United Kingdom government.”
“Obviously, European Union/United Kingdom relations are very important over time and they should be a relationship that’s built on sustained trust, they should be constructive,” he added.
“They should lead to the mutual benefit of citizens of the UK and citizens of the European Union.
“The relationship between Ireland and Great Britain is a fundamental one, the relationship between the two governments over 30 years has been central to the peace process, central to the architecture of the Good Friday Agreement.
“There’s an obligation on all parties to take those two fundamental sets of relationships into account before any action is taken.”
Negotiations between London and Brussels over the protocol remain deadlocked and there is mounting speculation that the UK government is poised to trigger Article 16 later this month.
Britain has repeatedly warned it will move to unilaterally suspend elements of the protocol if an agreed outcome is not reached.
The oversight role of the European Court of Justice (ECJ) in policing the operation of the protocol remains a key sticking point in the talks to resolve issues with its operation.
Mr Martin said it would be “reckless and irresponsible” to trigger Article 16, but refused to discuss the possibility of a trade war between the UK and the EU.
“I think we should be aware of self-fulfilling prophecies as well,” he said when asked if a trade war is looming.
“Nothing, as I say, is certain in that regard, because we’ve been here before and negotiations are still under way.”
He added: “There’s still engagement between the European Union and the UK.
“As I said in the Dáil last week, and I stand over my comments, I think it would be reckless and irresponsible to trigger Article 16.
“I believe that all parties need to take on board the fundamental importance of the relationship between the European Union and the United Kingdom, and the relationship between the Irish Government and the British government, in terms of what has happened over the last 30 years.”
Mr Martin said that triggering Article 16 would represent “a very serious issue in the context of both those relationships”.
But he added that negotiations are continuing and he is hopeful they will “bear fruit”.
He said the EU has offered “a very extensive set of measures” to smooth out issues with the operation of the protocol, adding “which I believe, if there’s a will, should lead to a positive conclusion to these talks”.
The Progressive Unionist Party this morning has published an extensive constitutional contribution. Our party supported the Belfast Agreement, but we are concerned the basis for that support has been erodehttps://t.co/ioUNp9QNrA pic.twitter.com/xYR2lh9oyv
— PUP (@OfficialPUP) November 8, 2021
Mr Martin has also called on the Progressive Unionist Party (PUP) to reconsider its decision to withdraw support for the Good Friday Agreement.
The PUP said on Monday that unionists should not support the peace deal because the consent principle, which is central to the 1998 accord, has been undermined by the protocol.
Mr Martin said: “I would say to the PUP and others to reconsider that decision. They have been a party supportive of the Good Friday Agreement.
“I would not agree with the comments that have been attributed to that party this morning in respect of the agreement itself, or in terms of the issue of consent.
“There’s been a transformation in relationships north/south, within Northern Ireland, over time.”