OPPOSITION Leader Bill Shorten and Greens Senator Sarah Hanson-Young will introduce bills which, if passed, would allow for same-sex marriage in Australia.
Mr Shorten's notice indicates the bill will be introduced to the House of Representatives next Monday at the next sitting of Parliament.
"I have given notice that I will move a Private Member's Bill in the House of Representatives on Monday which will finally bring about marriage equality in Australia," Mr Shorten posted to Facebook.
"It's time for our laws to reflect the values of modern Australia and to include everyone as equals."
"All MPs should have a free vote on this matter."
The Greens will bring on a vote for marriage equality in November.
Debate will be held next month before the November vote to be held on Greens Senator Sarah Hanson-Young's private members bill currently before the Senate.
"The Australian Greens welcomed the historic vote of 'yes' for same sex marriage in Ireland and the time is now right for Australia to follow suit," Sen Hanson-Young said.
"Gay and lesbian Australians deserve better than being treated as second-class citizens, it's well time the parliament acted."
Communications Minister Malcolm Turnbull, who is in favour of marriage equality, told the ABC Australia was out of step with many Western nations on the issue.
Deputy Labor Leader Tanya Plibersek also signed off on the notice and posted an image of their signatures to social media.
"Bill Shorten and I have just given formal notice we will present a bill for marriage equality to the Parliament next week," Ms Plibersek posted.
"The time for marriage equality in Australia has well and truly come.
"Together we can get this done."
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