NXT, led by South Australian Senator Nick Xenophon, released a statement this morning saying it wished to make clear its position on the proposed national poll: “We do not support it”.

“In our representative democracy we are paid to make decisions on behalf of Australians who have voted us into office,” it said. “This is a decision the Parliament should make now.

“The plebiscite, which in any event could be disregarded by the Parliament, could be in the order of $160 million or more. We believe this money could be better spent.”

The statement said NXT’s four elected members – Senator Xenophon, Senator Stirling Griff, Senator Skye Kakoschke-Moore and Member for Mayo Rebekha Sharkie – all supported marriage equality and were “ready to vote accordingly”.

That puts increased pressure on Labor to support the plebiscite or risk having no progress on the issue for three years. The Greens said last week they would try to block a national vote.

Labor Leader Bill Shorten has said caucus would consider the issue once the Opposition has the details, but he has also ramped up his rhetoric against the plebiscite, calling it the “second-best option”.

Shorten told a meeting of Labor’s shadow ministry this morning that the Government hadn’t made the case for the plebiscite.

“The quickest path to resolving this issue would be a vote in the parliament and that’s what we will be seeking to do in coming days and weeks,” he said.

Labor intends introducing a private bill legalising same-sex marriage.

Deputy Labor leader Tanya Plibersek said any delay in legalising same-sex marriage was on Prime Minister Malcolm Turnbull’s head.

“We could legislate marriage equality by the end of the week … if Malcolm Turnbull allowed it,” she told reporters today.

Labor Senate leader Penny Wong accused Mr Turnbull of lacking the courage to dump the policy.

She called on “fair-minded Australians” to continue campaigning for marriage equality and put pressure on Coalition MPs, “all those so-called moderates who are now not having the courage of their own convictions”.

Despite Labor and crossbench reluctance, the Government remains positive, with cabinet minister Mathias Corman saying it wasn’t a given that parliament would block a plebiscite.

Colleague Simon Birmingham said if the plebiscite was blocked, there wouldn’t be a same-sex marriage vote in parliament.

Government backbencher Warren Entsch, a long-time advocate for same-sex marriage, said if parliament blocked a plebiscite that should be the end of the matter until the next election.

“I’m not going to sit here and fiddle around year after year because somebody doesn’t get exactly what they want,” he told ABC radio, noting he’d copped a lot of flak for his stance over the years.

He also told The Cairns Post the $160 million price tag was the “cost of democracy”.

One Nation senator Pauline Hanson said a plebiscite should be held at the same time as the next election to save money

-with AAP