Opposition leader Bill Shorten has promised Australia he will be "constructive" in discussions over the marriage equality plebiscite, but is still not convinced of the merits of a national vote.
Shorten discussed the plebiscite, among other issues, with prime minister Malcolm Turnbull in a meeting on Thursday morning.
"I think most Australians know that a plebiscite is a second best option," Shorten said in a press conference.
"Let's see how we go in terms of persuading the parliament. I'm interested in resolving this issue," he said.
Shorten told reporters he listened carefully as the prime minister made his case, but is "not convinced" of the need for a plebiscite.
"What is the case for having a taxpayer-funded opinion poll which won't bind members of the government?" he asked. "Why is it some Australians have to have their relationships undergo a public opinion poll and many others don't?"
Asked specifically if Labor would vote against the plebiscite legislation, Shorten said "Let's cross that bridge when we get to it".
Shorten's comments indicate a softening in his stance since the election campaign, during which he branded the plebiscite a "grubby deal" with Coalition conservatives that he would not "sign up to".
"Just because Turnbull did a deal with the right wing of the Liberal party for an inferior option, why should I have to accept and sign up to Malcolm Turnbull’s grubby deal with the right wing of his party? I’m not going to," he told the National Press Club in June.
With senate results now finalised, it is clear that Labor, the Greens and the Nick Xenophon Team have sufficient numbers to block plebiscite enabling legislation in the upper house.
However, while each party has expressed their preference for a free vote, each has said more details are required before they can make a call on voting for or against.