The Taoiseach has said he hopes a solution to the UK-EU impasse on the Northern Ireland Protocol can be resolved after the Assembly poll.
It came as the Taoiseach warned that voters want politicians to return to powersharing after the Northern Ireland Assembly elections on May 5.
Micheal Martin was addressing an Irish parliamentary committee on the Good Friday Agreement, discussing his Government's project to boost cross-border ties on the island.
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There has speculation that the Queen's Speech on May 10 may include legislation to suspend the protocol unilaterally if a negotiated solution does not emerge.
Asked by Alliance Party MP Stephen Farry how the Irish Government might respond in such a case, Mr Martin said that he was loath to inflame debate during an election campaign.
The post-Brexit settlement for Northern Ireland has dominated politics in the region in recent years, amid unionist and loyalist anger at the creation of new checks on some goods moving across the Irish Sea from Great Britain.
Mr Martin said: "I'm conscious too, over the lifetime of Brexit, various things have been floated and some of them sink, some are refloated.
"And so I don't react immediately when I now begin to see certain articulations of certain ideas from time to time.
"I would say unilateralism doesn't work in the context of the Good Friday Agreement."
Mr Martin said the UK-Irish relationship that paved the way for the landmark agreement that ended the Troubles in Northern Ireland was "hand in glove, no surprises, heads up".
"Both governments are there as co-guarantors, even-handedly, fairly and objectively to support the process, and we will be playing our part in the aftermath of the election."
Mr Martin suggested a solution may be brokered on post-Brexit arrangements in Northern Ireland after polling day.
"My view is that United Kingdom Government and the European Union have within themselves, or within what's been discussed already, the landing zones to reach a resolution of all of those issues."
He said the EU had responded to some of the "legitimate" concerns raised about the protocol. "I think after the election, we hope we can pick up the baton again."
The Fianna Fail leader spoke at length about his hopes of boosting cross-border relationships, while also stressing the need for the Northern Ireland Executive to return after the Assembly election.
Voters will go to the polls in the Northern Ireland Assembly elections in a week.
There has been speculation that Sinn Fein could emerge as the largest political party in the Assembly.
There are also concerns that the DUP may refuse to return to powersharing amid opposition to the Northern Ireland Protocol and the response of the UK Government to post-Brexit arrangements for the region.
"Next week, the people of Northern Ireland will vote to provide a new democratic mandate for the devolved powersharing institutions at Stormont," he said.
"It is vital for the future of Northern Ireland and for relationships on these islands that the political parties take their mandates from the Assembly elections and move quickly to form a new executive.
"That is what the people of Northern Ireland want.
"This is a moment for political leaders to live up to the commitments of the Good Friday Agreement, which is overwhelmingly supported by people across this island.
The Fianna Fail leader called for political leadership to move beyond tensions over Brexit.
"Political leadership - by all with a role and responsibility - is also fundamental in getting beyond the issues around Brexit and the protocol that have hindered the peace process over the last six years.
"We need to return the focus to working collectively to support progress and prosperity for all in Northern Ireland and across this island, and to realising the opportunities in our societal, economic, cultural and political relationships through the framework of the Good Friday Agreement.
"These are the Government's objectives and responsibilities as a co-guarantor of the Good Friday Agreement."
Mr Martin and his Government have committed a total of €3.5 billion (£2.9 billion) for all-island, cross-border investment over the coming decade. Areas for co-operation include healthcare, education, tourism, transport and biodiversity.
The Irish premier said the aim is to deepen north-south and east-west relationships. He spoke of "good engagement" with UK Prime Minister Boris Johnson as well as politicians in Northern Ireland on the issue.
"The Government wants to see a deepening of beneficial co-operation and societal connections on the island, in all areas," he told the committee.
Taking questions from Irish parliamentarians, Mr Martin said the shared island initiative was simply about solving all-island problems. "It is not a Trojan horse, it is designed to pragmatically create opportunities to solve problems on the island," he said.
Quizzed by Fine Gael TDs Jennifer Carroll MacNeill and Fergus O'Dowd, Mr Martin insisted that "civic unionism" was engaging in the shared island project.
"No one is putting barriers up to the shared island programme."
He urged politicians from all parties, especially younger representatives, to discuss and talk about cross-border issues in a more formalised way.
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