The Boundary Commission is expected to recommend a shake-up of Dáil constituencies in a report due out later today.
The commission was established in April to examine if some constituencies have too few or too many TDs per head of population.
The existing boundaries were drawn based on the 2001 census figures, but commentators say population changes since then mean many constituencies do not comply with constitutional requirements.
Any changes could put the seats of some TDs at risk.