Independent ministers could vote against Fine Gael during a medicinal cannabis bill next week, writes Fiachra Ó Cionnaith of the Irish Examiner.
It comes as they insisted they will "exercise" their right to a free vote on the issue.
The decision was made by Independent Alliance TDs at today's Cabinet meeting.
As part of an opposition bill put down by the Anti-Austerity Alliance-People Before Profit group, the Dáil will on Thursday hold a two-hour debate on whether to allow cannabis use for specific medical reasons in order to help people in need.
The debate on the bill, which will undergo a Dáil vote next week, has been sought by AAA-PBP TDs Gino Kenny and Brid Smith in response to concerns patients with certain conditions are needlessly living with chronic pain.
The most high-profile of these cases is that of Ava Twomey, a six-year-old from Cork who has a rare condition called Dravets syndrome which can cause her to have up to 20 seizures a day.
Her mother Vera has campaigned for the right to give her daughter cannabidiol (CBD) oil, a form of medicinal marijuana, which relaxes her muscles and reduces the risk of seizures, saying without the law change her daughter's life is at risk.
At a post-cabinet briefing, an Independent Alliance spokesperson confirmed the five-strong Government group will "exercise" its right to a free vote in next week's Dáil ballot.
She said the Alliance is allowed to do this on issues outside the programme for Government, and that it did not seek permission from Fine Gael for the move.
While the Alliance will not decide on how it will vote next week until after Thursday's Dáil debate, it is likely the group will support the opposition bill.
Fine Gael has yet to decide on how it will vote, but a spokesperson last night made it clear Health Minister Simon Harris has "concerns about the bill". While the coalition parties are likely to take different positions, sources have confirmed that it is unlikely to cause a rift between them.
The situation emerged during a Cabinet meeting which also agreed to publish the heads of bill on the new Judicial Appointments legislation next week before the potential law change is published in January.
The move is designed to change the way in which judges are appointed after concerns were raised by Transport Minister Shane Ross.
However, before the bill is published, three judges will be moved from the insolvency court to the circuit court to fill existing gaps in the system.
Separately, Government will oppose Sinn Féin's upcoming bill on rent certainty and Independents4Change TD Clare Daly's bill on Thursday to reform solitary confinement in prisons.
Despite a public war of words over President Michael D Higgins' statement in response to the late former Cuban leader Fidel Castro's death, Cabinet did not officially discuss the situation.