It is now almost certain that the Longford Westmeath by-election will be held on May 23 with the local and European elections.
The Taoiseach Enda Kenny has confirmed it is on the Cabinet agenda, which would allow for the writ to be moved in the Dáil tomorrow afternoon.
It is to fill the vacancy created following the death of Nicky McFadden last month.
The move would also likely see the holding of a by-election in Dublin West on the same day, that seat is vacant after the resignation of Patrick Nulty.
Enda Kenny said: "The by-election has been caused by the unfortunate and tragic death of our friend Nicky McFadden.
"The Government changed the rules, insofar as there was a tendency to let by-elections drift for a very long period, they must now be held within six months.
"So the Government will consider the question of the Longford Westmeath by-election at its meeting tomorrow."