Irish deputy prime minister Simon Harris has written to political party leaders in Northern Ireland and the Republic seeking their views on Fine Gael's proposals for preparing for Irish unity. The party published its blueprint last week, which includes a suggestion to appoint a junior minister in the Irish government for north-south relations.

The letter was sent to DUP leader Gavin Robinson, UUP leader Jon Burrows, SDLP leader Claire Hanna, TUV leader Jim Allister and Alliance leader Naomi Long. In the Republic, it was sent to Taoiseach Micheal Martin, Sinn Fein leader Mary Lou McDonald, Aontu leader Peadar Toibin, Labour leader Ivana Bacik, Social Democrat acting leader Cian O'Callaghan, Independent Ireland leader Michael Collins, Green Party leader Roderic O'Gorman and Richard Boyd-Barrett of People Before Profit.

In the letter, Harris said no single party owns the discussion about the future of the island and that it must be an inclusive conversation grounded in the Good Friday Agreement and the principle of consent. He asked for views on the proposals and areas where further consideration may be required, acknowledging there will be differing views and difficult conversations.

Fine Gael also published a document by economist Stephen Kinsella, an adviser to Harris, which estimated the first-year cost of reunification for the Irish exchequer at between €3bn and €25bn. The report recommended a dedicated sovereign wealth fund for possible transitional costs and suggested that a plan for reunification must start as a plan for faster growth in Northern Ireland.

Separately, Taoiseach Micheal Martin, leader of Fianna Fail, has circulated a document to his parliamentary party outlining his own thoughts on how to prepare for a united Ireland.