Leo Varadkar

Delivering the opening speech to his party’s ard fheis yesterday, the Fine Gael leader said: “I believe in the unification of our island and I believe it can happen in my lifetime.”

However, he said unification “must not be the annexation of Northern Ireland” and would have to involve “a new constitution and one that reflects the diversity of a bi-national or multi-national state in which almost a million people are British”.

Mr Varadkar said: “We have to be willing to consider all that we’d be willing to change – new titles, shared symbols, how devolution in the North would fit into the new arrangements, a new Senate to strengthen the representation of minorities, the role and status of our languages, a new and closer relationship with the United Kingdom.

“We also need to map out how we can take the best of both jurisdictions and apply them across Ireland as a whole, perhaps our welfare and pensions system, their NHS to give just two examples.

“And also what might remain different, because unification is not assimilation, for example, perhaps education or maintaining two legal systems.”

He added: “Until these questions are answered, until we have a clear proposition to put to the people on both parts of our island, then a border poll is premature.”

A major 18-month research project recently concluded that it would be highly unwise for referendums on the constitutional future of Northern Ireland to be called without a clear plan for what follows.

The Working Group on Unification Referendums on the Island of Ireland, established by the UCL Constitution Unit, published the final report of its research into how any future referendums would best be conducted last month.