Taoiseach Micheál Martin has said he is “deeply concerned” about the resignation of DUP First Minister Paul Givan, saying it is “a very damaging move”.
Parties in Northern Ireland have called for an early election to take place after Stormont was plunged into a fresh powersharing crisis.
The move by the Lagan Valley MLA is part of the DUP’s escalating protest strategy against Brexit’s Northern Ireland Protocol.
It comes after DUP Agriculture Minister Edwin Poots ordered his officials to cease carrying out agri-food checks at Northern Ireland ports.
“The Taoiseach has consistently reiterated the importance of the institutions of the Good Friday Agreement, and the good functioning of the Northern Ireland Executive,” his spokesman said.
“We are deeply concerned about the latest developments and the resignation of DUP First Minister Paul Givan. This is a very damaging move.
“It is absolutely vital for peace and prosperity in Northern Ireland that the Executive is delivering for the people of Northern Ireland, particularly now as we emerge from the Covid pandemic.”
Mr Martin has reminded the UK government of their responsibility to implement the Protocol.
“The Protocol is part of an international treaty agreed and ratified by the UK and EU, to protect the Good Friday Agreement in all its dimensions,” his spokesman said.
“The UK has an obligation under international law, and under its own domestic law, to ensure it meets is obligations under the Protocol.
“The current talks between the EU and the UK and must be given every chance to succeed.
“The Commission has put forward serious proposals which directly address the concerns about outstanding issues on implementation of the Protocol.
“I would urge the DUP to return to full engagement with all the institutions of the Good Friday Agreement and avoid any action that could damage peace and stability in Northern Ireland.”
Minister for Foreign Affairs Simon Coveney said the decision was “deeply regrettable” and said efforts to address concerns about the Protocol raised by Unionists were ongoing.
He said: “We believe that people want to see a positive commitment from their political representatives to work with each other to resolve issues in Northern Ireland, rather than the creation of any new cliff edges or instability.
“There are of course ongoing discussions on the implementation of the Protocol between the EU and UK, where the Commission have put forward proposals directly addressing the concerns raised by Unionist representatives, including significantly reducing checks on goods moving between Great Britain and Northern Ireland.
“No positive agenda is served by undermining the institutions of the Good Friday Agreement and the resignation of the First Minister of course has wider implications for the Northern Ireland Executive and its important work.
“The focus of the Government now, as always, will be on working with the political parties and the British Government to support political stability in Northern Ireland, and the effective operation of all the institutions of the Good Friday Agreement, including the Executive and indeed the North South Ministerial Council which has also been impacted by the current political instability.
“I am in ongoing contact with the Secretary of State for Northern Ireland to discuss these developments.”