The legalisation of cannabis has been formally proposed by Independent TD Luke "Ming" Flanagan in the Dáil.
During a private members' motion put forward by the Technical Group this evening, Mr Flanagan said the debate is "going mainstream".
He said that despite the issue being described as "radical" in Dáil Éireann, the vast majority of the public "are with it".
Fianna Fáil's Niall Collins said the principle that cannabis should be legalised is simply indefensible, as the health and social risks are far too great to countenance.
He said Mr Flanagan's bill is a deeply flawed measure reflecting faulty assumptions.
Sinn Féin's Sandra McLellan said her party will not be voting in favour of the bill, but it is something that should be looked at it in a calm and measured way.
The debate was adjourned until 9.30am tomorrow morning.