Liberal senator Cory Bernardi says Malcolm Turnbull should choose between the frontbench and publicly backing gay marriage.
Controversial Liberal Senator Cory Bernardi has called for Malcolm Turnbull's ministerial scalp if he continues to publicly support same sex marriage.
The communications minister reiterated his support for marriage equality over the weekend, saying it was likely the coalition government would allow a conscience vote on gay marriage.
His Liberal colleague Senator Bernardi says there's no room for frontbenchers talk up their personal views if it differs from the party's official line.
"If Malcolm Turnbull wants to talk about fringe issues outside party policy, he should resign from the frontbench," Senator Bernardi told the ABC on Monday.
Last week, the High Court ruled the ACT's gay marriage laws were invalid, turing attention back to federal parliament with its legislative power to provide for same sex marriage.
Prime Minister Tony Abbott says allowing coalition MPs a free vote on same sex marriage would be a matter for the party room.
Mr Turnbull supports gay marriage but has declined a request from deputy Labor leader Tanya Plibersek to co-sponsor a gay marriage bill.
Senator Bernardi is a conservative Christian who infamously linked bestiality to gay marriage during a Senate debate last year.