The Australian Labor party leader has said that Prime Minister Malcolm Turnbull is a “traitor to the cause” if he will not allow a debate on same-sex marriage.

Bill Shorten made the comments about Turnbull saying he should use the upcoming session of Parliament which commences on 18 April, to debate the measure.

Speaking to the Guardian, Shorten said Turbull had “run out of excuses to make marriage equality a reality”.

“Malcolm Turnbull can use the recalled sessions of parliament for a free vote on marriage equality. His delaying tactics aren’t fooling anyone,” he said.

“If he refuses to do so it will prove once and for all that he is a traitor to the cause.”

Parliament was recalled by Turnbull in order to debate legislation for the Australian Building and Construction Commission.

Other legislation may be debated by the Senate, where the Coalition Government does not hold a majority.

Turnbull was accused of trying to kick same-sex marriage into the long grass earlier this year – by refusing to clarify a timetable for a public vote.

Even though a majority of MPs are in favour of equality, Coalition PM Malcolm Turnbull has refused to allow a free Parliamentary vote – instead calling for a public ‘plebiscite’ which will stall the issue until after the next election.

The idea of a plebiscite came before Turnbull took office, as previous Prime Minister Tony Abbott also refused to allow Coalition MPs a free vote on the issue.

Abbott had insisted that Coalition MPs would not have a free vote on the issue, and that a plebiscite was the only way to settle it.

However when Malcolm Turnbull took over as Prime Minister in November when Abbott was ousted, he maintained that a plebiscite would take place.

Previous Prime Minister Tony Abbott insisted on a plebiscite

This all comes despite an estimated cost of a plebiscite being AUD$160 million, and mounting pressure to allow a conscience vote on the issue.

Turnbull, who is reportedly a regular attendee of Sydney Mardi Gras, earlier this month became the first sitting PM to attend the festivities.