Tony Abbott has been confronted over gay marriage with MPs defying his wishes and bringing on a debate in the party room on Tuesday morning.

The weekly meeting, which was supposed to focus on the government's climate change policy, has discussed whether Liberal MPs should be allowed a conscience vote on the issue.

Gay marriage proponent Warren Entsch instigated the discussion. There was no resolution. Sky News reported however there would be further debate at a later date.

Warren Entsch places a flower at the seat of the late Don Randall member for Canning at Parliament House in Canberra on Monday. Andrew Meares

Mr Entsch plans to introduce a private members bill next week, which will be co-sponsored by Labor. Presently, Liberal MPs are bound to vote against gay marriage.

Mr Entsch, who met Mr Abbott on Monday, intends to lodge notice of the bill later Tuesday. A Liberal-dominated committee which selects private members bill for debate in the House of Representatives must still give it approval.