The Scottish government has threatened to take action against Irish fishing vessels that fish in the area around Rockall, which is disputed territory 400km northwest of Ireland.
Ownership of Rockall has long been a source of dispute between the Irish and UK authorities, but Irish fishing vessels regularly fish in the area.
In a statement to RTÉ News, a spokesperson for the Scottish government said it is obliged to defend the interests of Scottish fishermen.
It said it has told the Irish Government to warn Irish fishing vessels not to fish illegally to remove the need for Scotland to take enforcement action.
The spokesperson said Irish vessels, as with any non-UK vessels, have never been allowed to fish in this way in the UK's territorial sea around Rockall and, despite undertaking extensive discussions with the Irish authorities on the matter, it is disappointing that this activity continues.
While Ireland does not recognise British sovereignty over Rockall, the State has never claimed sovereignty for itself.
The Irish Government's position is that Rockall should be viewed as a "rock for all", arguing there is no merit in any country claiming sovereignty over Rockall or any other uninhabitable sea stacks.
Ireland calculates that Rockall lies 230 nautical miles northwest of Donegal.
However, Tánaiste Simon Coveney and Minister for Agriculture, Food and the Marine Michael Creed have rejected the unilateral threat of "enforcement action" against Irish fishing vessels fishing within 12 miles of Rockall.
The Department of Agriculture, Food and the Marine said: "The position of the Irish Government has been and remains that the waters around Rockall form part of union waters under the Common Fisheries Policy, to which the principle of equal access for the vessels of all EU Member States applies.
"Irish vessels have operated unhindered in the Rockall zone for many decades fishing haddock, squid and other species."
Mr Creed said: "The Tánaiste and I have worked very closely to avoid a situation whereby Irish fishing vessels who have been and continue to fish for haddock, squid and other species in the 12-mile area around Rockall, are under the unwarranted threat of 'enforcement action' by the Scottish government.
"However, following this sustained unilateral action by them, I have no option but to put our fishing industry on notice of the stated intention of the Scottish government."
Mr Coveney said: "The longstanding position of the Irish Government is that Irish vessels are entitled to access to Rockall waters.
"We have never recognised UK sovereignty over Rockall and accordingly we have not recognised a territorial sea around it either."
"We have tried to work positively with the Scottish authorities and to deal with sensitive issues that flow from it in a spirit of kinship and collaboration.
"We very much regret that matters have reached this point and intend to do everything possible to achieve a satisfactory resolution."
Fianna Fáil's Pat the Cope Gallagher, has described the Scottish announcement as a "unilateral illegal action" and a "very serious matter".
The Donegal deputy said he would be raising the matter with Taoiseach Leo Varadkar when the Dáil returns on Tuesday.
Adopting a hardline position, the Scottish government has claimed that Irish vessels have "never been allowed to fish" in what it terms "the UK's territorial sea around Rockall".
A spokesperson asserted that there has recently been "an increase in that illegal activity" and claimed "it is our duty and obligation to defend the interests of Scottish fisheries".
The spokesperson added it had been "disappointed" that this so-called illegal fishing was taking place, despite what was termed "extensive discussions with the Irish authorities on the matter".
The spokesperson stated "enforcement action" would be required "to protect our fisheries interests" if Irish vessels fished off Rockall.