The UK's Brexit negotiating stance cannot just be "a series of demands which appeal to people in Peterborough", a former Irish prime minister has warned.
John Bruton made the comments at the House of Lords EU Select Committee.
He said the UK would need to take an imaginative approach which appealed to mutual self-interest.
"The negotiating bid should be framed as what Britain wants to do to help the EU prosper and the UK prosper."
Mr Bruton, who also served as EU ambassador to the US, added that in his experience the best way to get anything done in Europe is to present your position as good for Europe as a whole.
He said it is "very easy to see what's good for yourself" but more difficult to ask "what's in this for Slovenia?"
Mr Bruton was giving evidence alongside Bertie Ahern, another former Irish prime minister.
Mr Ahern dismissed a recent suggestion that Irish ports and airports would become proxy points of entry into the UK and a type of frontier for British immigration checks.
"I quite frankly just found that unbelievable," he said.
"To put that suggestion forward is a total lack of understanding of how people think, north and south, of either tradition. It just would not happen."