Northern Ireland's 18 MPs are to be allowed to attend committee meetings in the Dublin parliament whenever they want for the first time.
Oireachtas committees are cross-party parliamentary bodies
One of these is the newly-formed Joint Committee on the Implementation of the Good Friday Agreement.
MPs will not be allowed to vote. The privilege is likely to be used by nationalists but ignored by unionists.
SDLP leader Mark Durkan said attending committees was "an additional means of engagement on a north/south basis".
He warned it should be no substitute for a north/south parliamentary forum, as envisaged by the Agreement.
Oireachtas committees are cross-party parliamentary bodies made up of Dail and Seanad members.
They shadow various departments and deal with a range of investigations to advise the government.
Sinn Fein has made longstanding calls for speaking rights for Westminster MPs in the Dail and Seanad.
This was backed by an Oireachtas committee in 2002, but the process to implement this has stalled.