A "yes" vote in a proposed 2017 plebiscite on same-sex marriage equality would deliver the change immediately, with legislation to be put to Parliament before the next election under a new plan being considered by Prime Minister Malcolm Turnbull.

That legislation would set out the precise wording as well as mandating the timetable for the public vote.

In a sudden acceleration of the reform process that risks inflaming tensions with religious conservatives and most Nationals, the Prime Minister has indicated that the plebiscite, while technically non-binding, would itself be the decider of the controversial reform.

Queensland Liberal Warren Entsch said he had already discussed a plan with the Prime Minister that involved passing contingent amendments to the Marriage Act to achieve same-sex marriage equality, but with the legal force of those changes reliant on majority public support via the plebiscite.