South Australia’s outgoing premier Mike Rann has called for full marriage equality.

Speaking in Adelaide yesterday at the end of the Festival of Ideas, Mr Rann said that the status quo was “discrimination” and that civil unions are a “halfway house”.

The Labor politician is to step down on October 20th. This is the first time in his 25-year political career he has backed gay marriage.

He said: “Same-sex marriage is an idea whose time has well and truly arrived. Not to address this discrimination will diminish us as a nation, as a tolerant community.”

According to ABC News, he added: “This must be through the institution of marriage at a federal level. Rather than the halfway house of civil unions, as recently introduced in some other states, as well as in New Zealand and the UK.

“It is, quite simply, unfair to prevent same-sex couples from having their relationship, a union that is viewed as equal in every other aspect of the law, being recognised as a legal marriage,” he said.

“It only serves to undermine the legitimacy of their relationship, and their family. What are we so afraid of? Why is this next step so threatening?”

Federal Labor will debate the issue of gay marriage at its December conference. Prime minister Julia Gillard is against gay marriage.

Former state Labor deputy leader Ralph Clarke, who said Mr Rann should have given his support sooner, told ABC News’ The World Today that the conference would vote “overwhelmingly in favour” of gay marriage, leaving the government to decide a timetable of implementation.

The party’s Queensland, Tasmania, West Australia, South Australia, Victoria, ACT and Northern Territory branches have all passed motions in support of marriage equality.