Campaigning has escalated around Australia ahead of a bill to legalise gay marriage, with thousands rallying in support of marriage equality over the weekend.
Streets were closed off in the centre of Sydney on Sunday as more than 4000 people took part in a march and called on the federal parliament to pass a marriage bill that will be introduced on Tuesday.
Many in the crowd wore rainbow colours and waved flags and placards.
Speakers included representatives of the Greens, activist group GetUp, the Maritime Union of Australia and march organisers Community Action Against Homophobia.
Transgender woman Stephanie McCarthy told the crowd politicians expected the issue of gay marriage was "just going to go away".
"It's not going to go away because we are not going to let it," Ms McCarthy said.
Esther and Mark Holloway, both aged 32, attended the rally with their 11-month-old daughter Maya.
Ms Holloway said she and her husband wanted to raise their daughter in a "future where she has options".
The Sydney rally and another in Perth, attended by about 500 people on Sunday followed large protest marches in support of equality in Brisbane and Hobart.
Organisers claimed a turnout of 5000 people in Brisbane and 1500 in Hobart on Saturday.
Campaigners for and against marriage equality have ramped up their activities in the lead up to the introduction on Tuesday of a cross-party bill to legalise gay marriage.
The private member's bill is co-sponsored by Liberal MPs Warren Entsch and Teresa Gambaro, and seconded by Labor backbencher Terri Butler.
The Liberal party room will decide on whether there will be a free vote on the issue once the bill is moved in parliament.
The Australian Marriage Equality group has launched a series of television advertisements featuring celebrities and AFL footballers calling for legalisation, and an online campaign with the hashtag #WeCanDoThis.
Actor Hugo Weaving and comedian Julia Morris appear in ads that ask "what's all the fuss?" and state "it's about giving everyone a fair go".
AME has created a campaign website complete with a countdown clock, as has Marriage Alliance, a group opposed to gay marriage, which on Friday complained the Seven Network and Network Ten had refused to run its ads.
Marriage Alliance spokeswoman Sophie York called for the right to a "fair go".
"Has political correctness or the power of a certain lobby group reached so far down that it now erodes the once proud Australian `fair-go' character that it is preventing ordinary Australians from having a voice?" Ms York said in a statement.
Marriage Alliance's campaign, which uses the line "it's not as simple as you think", says legislating to allow gay marriage may affect people's rights across the entire community.