Simultaneous marriage equality rallies around Australia last weekend wrapped up a landmark week for the marriage equality cause.

The Brisbane rally, organised by the local branch of Equal Love, saw guest speakers and musical drag performances entertain a crowd of more than a thousand supporters in Queens Park.

Michael James, recognised as one half of last year's Rip & Roll safe-sex campaign, spoke highly of the civil union he shares with his partner but said the same-sex marriage fight was paramount.

"Make sure everyone you know is getting behind this cause and speaking loud and clear to everyone in this country that needs to hear us," he told the crowd. "Hear our words and do what is right."

"Our politicians cannot do anything if there is not a clear, direct voice from as many members of this community as possible asking for what we want and when we want it."

The rally was followed by a loud, colourful march through the Brisbane CBD. A police escort diverted traffic as the crowd chanted and warmly greeted pedestrians.

One couple marched with signs reading "Newman Be Civil, Don't Mess With Our Union," a reference to Premier Campbell Newman's pre-election threats to strip 400 Queensland couples of their civil unions.

The Brisbane rally's turnout was matched at capital cities around the country.

Earlier in the week Barack Obama set off a wave of worldwide media coverage with the announcement of his personal support for same sex marriage. Obama's announcement came days after the passing of a bill in North Carolina that explicitly banned gay marriage in that state.

New Zealand Prime Minister John Key also spoke in favour of same-sex marriage this week, leaving both Julia Gillard and Tony Abbott's continuing opposition to the issue in stark contrast.

Greens MP Sarah Hanson-Young appeared at the Adelaide rally on Saturday and spoke of the clear public support for her marriage equality bill, one of three in parliament.

"Ordinary Australians are giving the Labor and Coalition leaders a strong but positive message that it's time they removed discrimination from the Marriage Act," Hanson-Young told reporters.

"The people on the streets are saying 'Yes we can,' and it's time for Julia Gillard and Tony Abbott to do the same."

Attorney General Nicola Roxon also confirmed her support for same sex marriage at a media conference in Melbourne on Saturday. Roxon said she will vote in favour of marriage equality when the time comes later this year.

"I think that it's an issue that's time is coming and I think many people - me included - have, over time, been persuaded of the importance of this," she said.