Scott Morrison and Malcolm Turnbull in parliament.  Federal cabinet has yet to decide any of the details of a national vote on same-sex marriage including its timing or the question, Treasurer Scott Morrison says.  Attorney-General George Brandis sparked confusion at the weekend when he said the plebiscite to change the Marriage Act would be held later this year.  But Prime Minister Malcolm Turnbull said it would be held as soon as possible after the federal election, likely to be this year.  Mr Morrison, who opposes same-sex marriage, said none of the details of the vote had been decided beyond the fact that a plebiscite would be held.  "There's no change to the policy - the policy is to have a plebiscite," he told 2GB radio on Monday.  "The details of how it is constructed and the question and all of those sorts of things - that is still detail to be worked through and that will go through the normal cabinet process, including the ultimate timing of these things."  Senator Brandis said on Monday he did not see any disparity between his comments and those of the prime minister.  "I said we want to have this by the end of the year, Malcolm Turnbull said he wanted it to be as soon as possible after the election - I don't think those are inconsistent positions," he said.  Senator Brandis said the design of the plebiscite would be decided "closer to the time".  Asked whether he would take a backseat approach to the plebiscite, Mr Morrison said: "I don't plan to keep my opinion to myself on these issues and I don't think anyone should - that's the whole point of having a plebiscite."  Senator Brandis said he had no problem with coalition MPs voting against the law change even in the event of a majority "yes" vote.  "I think that is entirely a matter between them and their conscience," he said.  Dumped cabinet minister Eric Abetz, who opposes same-sex marriage and has insisted he won't be bound by the plebiscite result, said the Brandis comments came as a surprise.  "These are matters that the party room still has to sort out in some detail," he told The Australian.  Opposition Leader Bill Shorten said the quickest way to achieve same-sex marriage would be to vote on it next week when parliament sits.  "You have to ask yourself why we are having a plebiscite at all," Mr Shorten told reporters in the Tasmanian town of Deloraine.  A Labor government would have a bill to legalise same-sex marriage before parliament within 100 days of the election.  A bill with cross-party support is before the House of Representatives.
Labor has hit out at confusion within the Turnbull government over the timing of a proposed plebiscite on gay marriage.