Fine Gael's Noel Rock says the doomsday clock on the current Government has shortened.
The Dublin North-West TD believes Fianna Fáil's agreement to support the coalition will not last its full term.
Speaking about the current controversy surrounding Maurice McCabe and a motion of no confidence by Sinn Féin, Mr Rock said: "Whether we survive the motion or not, there's no question that the doomsday clock has shortened somewhat".
"I can't imagine Fianna Fáil continuing to support the arrangement (to support Government).
"We always kind of knew that something like this could happen - something that is out of control, that started before the Government came into existence", he added, referring to the McCabe scandal.
"It's been badly handled - with a lack of leadership and a lack of control. The best case scenario is that we get through tomorrow and the motion of no confidence", he told Newstalk.com.
Mr Rock tweeted Monday that he was "back to the doors" with a team of people from his constituency, but he says this is nothing new.
"We had one of the youngest, most energetic campaigns in the last election, and people were keen to get back to the doors.
"I'm always on the doors and last night we had 26 people out."
Back to the doors tonight. Best team in the business. pic.twitter.com/K4kmuUsFB5
— Noel Rock (@NoelRock) February 13, 2017
He also says while there is no appetite for a general election from the public, things need to change.
"Most Irish people don't want an election right now" he said, before adding that he believes the Government is "potentially tipping towards an election".
"We'll get through tomorrow and we need a clear, sustained focus".
Mr Rock also wants to see Taoiseach Enda Kenny to set out a timeline for when he will step down.
Asked who he wants to see lead the party, Mr Rock replied: "In my opinion, Leo (Varadkar) and Simon (Coveney) would represent a good generational change."
