Labor leader Bill Shorten aims to stop the Australian government’s planned plebiscite on the issue.

The Australian Opposition has introduced legislation to parliament that aims to legalise same-sex marriage, claiming it is a chance for the parliament to “prove its worth and fulfil its purpose”.

“Today we can bring a new measure of hope and happiness to the lives of tens of thousands of Australians whose love has been denied equality under the law for too long,” Bill Shorten said as he introduced the private bill on Monday.

“Why should the children of LGBTI Australians be denied the formal recognition of their parents’ relationship?”

Mr Shorten later claimed that Australia was “lagging behind” many other countries when it comes to same-sex marriage legislation.

“We’re falling short of our own national sense of self,” he said.

He said his party also fears an increase in homophobia and anti-gay behaviour as people campaign to stop same-sex marriage be legalised.

“(It) risks providing a platform for prejudice and a megaphone for hate speech,” Mr Shorten said.

The private bill comes as the issue of same-sex marriage continues to divide politicians in Australia.

The country’s right-wing Prime Minister Malcolm Turnbull has avoided a free Parliamentary vote on equal marriage, instead making plans to take the issue to the public in a non-binding plebiscite to avoid a rift with his own conservative anti-LGBT MPs.

However, Mr Shorten says “a plebiscite would represent a fundamental failure of this parliament to do its job.”

The proposal has been repeatedly blocked by opposition parties, who support equal marriage but see a plebiscite as a costly measure inviting homophobic debate.

Under Labor’s rival plan, equal marriage would go straight to a free vote in Parliament, paving the ways for marriages to begin much sooner without requiring a plebiscite.