The SDLP has accepted an invitation to attend the centenary church service in Armagh later this month organised by Irish church leaders.
The prayer service, which the Queen is expected to attend, has been organised by the four main churches in Northern Ireland to mark the centenary of the creation of Northern Ireland.
The service is timed to coincide with the centenary of the formation of Northern Ireland in 1921.
Irish president Michael D Higgins turned down an invitation to the service and Sinn Féin has now confirmed it would not be attending.
It will be held at St Patrick’s Church of Ireland cathedral on 21 October. It is being described as a service of reflection and hope, to mark the centenary of the partition of Ireland and the formation of Northern Ireland.
The SDLP has not confirmed which member of the party will be attending.