The Ulster Unionist Party is set to break with history today by taking part in a meeting of the British-Irish Inter-Parliamentary Body in Newcastle, England.
The body was set up under the Good Friday Agreement to boost relations between the Dáil and Westminster, as well as the national assemblies in the North, Scotland and Wales.
Unionists have so far refused to participate in any of its meetings, but the UUP will be represented today by Ken Maginnis, a member of the British House of Lords.
The Newcastle gathering is set to hear calls from politicians on both sides of the Irish Sea for the British government to release intelligence files on the Omagh bombing.
The families of the victims are seeking access to intelligence information as part of their civil action against a number of men suspected of involvement in the 1998 attack.