Time for a little gunboat diplomacy perhaps?
Dublin and London have been at odds since partition over territorial possession of Lough Foyle, the body of salt water that divides counties Derry and Donegal.
And unlike the Great Lakes, which have map lines delineating American and Canadian waters, Lough Foyle has no line on any map at all.
That’s because the British reckon all of it belongs to them.
The dispute over Foyle has been smoldering since 1922 – that’s if it is possible for water to smolder.
Both the British government and Irish Free State government laid claim to the entire body of water.
The Irish claim has been maintained down the years by successive governments of the Republic.
London acknowledges the Irish claim, but won’t recognize it.
Indeed, it states that all of Lough Foyle falls within the United Kingdom.
Which would seem to suggest that if you were on the Donegal side with one foot in the water and one foot on land you would be straddling two jurisdictions.
The straddle, presumably, will become wider post-Brexit.
There are no current negotiations aimed at resolving the dispute.
And, fair to say, the dispute doesn’t really get in the way of day to day activities on the water, or along the Lough’s banks.
That’s because regulation of activities in Lough Foyle falls to the Loughs Agency, a cross-border body established under the Good Friday Agreement of 1998.
Now, however, the “border” bit has run ahead of the “cross” bit – this after Northern Ireland Secretary of State, James Brokenshire, in response to a parliamentary question, stated that his government's position was, and remains, that "the whole of Lough Foyle is within the UK.”
This statement, suffice it to say, has caused ripples.
“Brexit has sparked its first territorial dispute - reigniting an ancient row over the ownership of Lough Foyle,” reported The News, a paper published in Portsmouth, England, a town with an abiding historical interest in all things watery.
“Claims over the vast estuary between Co. Derry in Northern Ireland and Co. Donegal in the Republic of Ireland have been made since the island was partitioned almost a century ago,” the report stated before going on to add that Carlingford Lough, which rests between Louth and Down, is also contested.
The report stated that “in the wake of the UK's vote to leave the European Union” Northern Ireland Secretary of State James Brokenshire had reasserted London's claim over the entirety of Lough Foyle.
In response, Dublin had issued a fresh declaration saying it did not accept the claim and does not see Lough Foyle's disputed ownership being put on the table as part of the Brexit negotiations.
Mr. Brokenshire, according to The News, was asked in a parliamentary question how fishing rights would be decided in both Lough Foyle and Carlingford Lough after the UK leaves the EU.
Added the report: “The Conservative minister said London is committed to withdrawing from the EU Common Fisheries Policy and putting a new fisheries regime in place.
“But no actual decisions have yet been taken, he said, adding that the UK was bound by international law.
“Asked specifically about Lough Foyle he added: ‘The Government's position remains that the whole of Lough Foyle is within the UK.’"
Dublin's Department of Foreign Affairs swiftly rejected the claim, the report said.
“Ireland has never accepted the UK's claim to the whole of Lough Foyle," the department said in a statement.
Dublin said both governments agreed to try and resolve the ongoing row over both Lough Foyle and Carlingford Lough during talks in 2011 between the then minister for foreign affairs and the British foreign secretary.
"Since that time a series of meetings have taken place at official level between the Foreign and Commonwealth Office and the Department of Foreign Affairs and Trade," the department statement added.
"The issues involved are complex and involve a range of different actors, including the Crown Estates.”
The latest British claim is not balm on troubled waters as far Donegal Sinn Féin Senator, Pádraig MacLochlainn, is concerned.
Far from it.
In a statement he called on the Minister for Foreign Affairs, Charlie Flanagan, to challenge the latest pronouncement from London on the ownership of Lough Foyle.
"This is an arrogant and provocative pronouncement from James Brokenshire, but unfortunately it is a repeat of previous pronouncements and again and again, previous Irish governments have failed to sort it out,” MacLochlainn said.
And he added: “I am calling on the Minister for Foreign Affairs, Charlie Flanagan, to immediately challenge this assertion on behalf of the Irish people.
“I am also calling on Minister Flanagan to clarify what is the status of the negotiations between the two governments on the ownership of the Lough.
“The Loughs Agency tasked with responsibility for managing Lough Foyle by both governments have been repeatedly calling for a resolution so that the real tourism and fisheries potential of the Lough can be fully realized.
“Minister Flanagan also needs to clearly outline why agreement has not been reached to date.”
This article first appeared in the Irish Echo. For more stories, visit their website here.