The Taoiseach Enda Kenny will attend an extraordinary meeting of the British Irish Council in Wales today, where he will meet the First Minister for Wales, Carwyn Jones.
The implications of Britain leaving the European Union will top the agenda.
Political leaders from Ireland and Britain will convene in Cardiff today for the key talks.
The British-Irish Council (BIC) summit was called for by Wales' First Minister Carwyn Jones and will see officials discuss the implications of Brexit.
The meeting will be attended by leaders and ministers from the eight BIC member administrations: the Irish and UK governments, the devolved administrations of Northern Ireland, Scotland and Wales and the governments of Jersey, Guernsey and the Isle of Man.
Speaking ahead of the event, Mr Jones said: "I called for and convened this summit so leaders and ministers from across Britain and Ireland have the opportunity to discuss the fundamental changes that will be brought about by the result of the EU referendum.
"The council plays a unique and important role in developing positive relationships between its members.
"During this tumultuous time, it is more important than ever to maintain the strength of this relationship and work together to map out a successful way forward."
The BIC was established under the Belfast Agreement of 1998, which set out the basis for the Northern Ireland peace process.
The council develops links between the member administrations and provides a forum to exchange information and foster collaboration across the islands.
Among those at the meeting today will be Scotland's First Minister Nicola Sturgeon and Secretary of State for Northern Ireland James Brokenshire.