John Byrne rans Byrne's Hill Street, a popular haunt in the town.
A local publican has hit out at British Foreign Secretary Boris Johnson, claiming the Tory MP is "not in the real world."
John Byrne, owner of Byrne's Number 10 of Hill Street in Dundalk is the fifth generation of family that has traded at the premises that first opened as a licensed grocer in 1895.
Speaking to BBC Radio 4's Today programme, in Ireland producing a special segment on how Brexit may impact on the border between Northern Ireland and the Republic, John didn't hold back when it came to his feelings about Boris Johnson.
"Things have progressing enormously since, I'm going to the say, the 80s until now. We cannot go back to not having simple transition," he said.
When presenter Sarah Montague asked the pub landlord what he made of Johnson's remarks that the Irish border could follow a similar path to that of congestion charge areas in London, Byrne was scathing.
"I think he's not right in the head," he said. "He's not in the real world if that's what he thinks. Has he ever actually stood along the border here to understand what it's physically like?
On Wednesday, the Tory MP remarked that there was no border between Islington, Camden and Westminster, referring to congestion charges in place in central London. "I think it's a very relevant comparison," he said.
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