Taoiseach Micheál Martin has said it will be "very problematic" if the UK again extends unilaterally the grace period for Northern Ireland Protocol checks.
But speaking on the Trevor Phillips on Sunday programme on Sky News, Mr Martin also insisted a breakthrough between the EU and UK was still possible "if there's a will there on both sides".
His comments came after Boris Johnson escalated his dispute with the European Union by warning he will do whatever it takes to keep goods flowing from Great Britain to Northern Ireland.
Following talks with the EU's key figures on Saturday, the British prime minister said he would not hesitate to take unilateral action to protect the position of Northern Ireland in the increasingly bitter row over post-Brexit trading arrangements.
The row – dubbed the “sausage war” – could mean chilled meats will not be shipped across the Irish Sea because of EU rules after the end of the month.
The UK is considering extending the current grace period without the consent of Brussels to ensure that sausages and mince can continue to reach Northern Ireland's shops.
But Mr Martin told Sky News that the “channels do exist to get this resolved”.
He added: “In particular, the Sefcovic/Frost process should be fully explored and optimised to get an agreement and I think the prospects, in my view, if there’s a will there on both sides, and there is a will there from the European Union side I know that, I detect from the British prime minister Boris Johnson that the British government is anxious to get a resolution of this, so I think we should work at it.”
Mr Martin said he believed an SPS agreement (on plant and animal health measures) could remove 80 per cent of protocol checks.
When asked about the possibility of the UK unilaterally extending the grace period for checks, Mr Martin said: “I think it will be very problematic because it’s not about sausages per se, it really is about the fact that an agreement had been entered into, not too long ago, signed off by the British government with the European Union.
"If there's consistent, unilateral deviation from that agreement, that clearly undermines the broader relationship between the European Union and the United Kingdom, which is in nobody's interest and therefore that's why the UK with the EU have to work very hard now in the coming weeks.
“I know the European Union are anxious to resolve this and want to resolve it but they need to see a similar reciprocity from the UK side.”
When asked if the protocol is undermining Northern Ireland’s place within the UK, Mr Martin said: “We’ve never seen the protocol as a constitutional issue, it doesn’t in any way interfere with the constitutional status of Northern Ireland as defined and articulated in the Good Friday [Belfast] Agreement.
"We're very clear from the Irish Government perspective on that, but we do believe in seamless trade on the island of Ireland, it makes sense. We believe in seamless trade insofar as we possibly can between the United Kingdom and Northern Ireland."
Poots and Macron
DUP Leader Edwin Poots said he has sent French president Emmanuel Macron a copy of the Belfast Agreement to remind him about Northern Ireland's constitutional status.
The move came after the French president reportedly suggested Northern Ireland was not part of the UK during his talks with Mr Johnson in the margins of the G7 summit.
The exchange led foreign secretary Dominic Raab to tell Sky News: “We have serially seen senior EU figures talk about Northern Ireland as if it was some kind of different country to the UK. It is not only offensive, it has real-world effects on the communities in Northern Ireland, creates great concern, great consternation.
“Could you imagine if we talked about Catalonia, the Flemish part of Belgium, one of the lander in Germany, northern Italy, Corsica in France as different countries? We need a bit of respect here.”
In response to Mr Macron’s reported remarks, Mr Poots said he had written to him and attached a copy of the 1998 Belfast (Good Friday) Agreement.
Mr Poots said: “Emmanuel Macron’s suggestion that Northern Ireland is not part of the United Kingdom is offensive and demands a statement from the French administration which recognises Northern Ireland’s constitutional status.
“This also exposes the ignorance which lies at the heart of the EU. They seem blind to the destruction the protocol has caused to the Belfast Agreement.
“It’s five years since the [Brexit] referendum. Northern Ireland has been centre stage for most of that time yet the most powerful man in one of the most powerful EU countries still doesn’t realise that Northern Ireland is part of the United Kingdom. It’s incredible.”
The DUP leader added: “Key leaders in the European Union clearly do not even understand the basics let alone the finer details.
“It is time for the Government to stop talking about fixes to the protocol and get on with taking the necessary steps to remove it.”
‘Bellicose words’
Meanwhile, a Government Minister has said that “bellicose words” and a “heightening of rhetoric” are often part of deal negotiations as he expressed confidence that agreement would be reached on the Northern Ireland protocol.
Minister of State for Communications Ossian Smyth said that what is going to resolve the difficulties “is the hard work, the boring work of working out all the details of these agreements”.
Speaking on RTÉ’s The Week in Politics, Mr Smyth said: “I think sometimes there’s a heightening of rhetoric just before we get to that point where we make an agreement.
“Agreement is going to be done with hard spade work instead of big walking-out words. It’s not going to be unilateral action that’s going to happen. What’s going to happen is negotiated agreement.”
He said that “with all negotiations there is often a heightening of tensions, bellicose words”.
“Perhaps people who hoped Brexit would free them from that are disappointed that they find they’re involved in prolonged negotiations with the EU again.
“But there’s no other way out. The only thing we can do is to negotiate our way into a peaceful relationship between our countries and also to have trade prospering.” – Additional reporting: PA
