The South Australian parliament has been urged to pass same-sex marriage laws after gay MP Ian Hunter had to go to Spain to marry his long-time partner.

On Thursday Mr Hunter because the first gay Australian politician to marry while in office when he wed Leith Semmens in the town of Jun, near the southern city of Granada.

The pair, together for 22 years, flew half-way around the world to tie the knot, two months after the federal parliament voted down same-sex marriage legislation.

Mr Hunter, the social inclusion minister, said the decision to travel to Spain, which has allowed same-sex couples to marry since 2005, was about finally being able to express his love for his partner in front of the people who were important to him.

He said the pair had decided they couldn't wait for their own country to approve their union.

"Without a doubt it's inevitable in Australia, but you're looking at six or seven years, and me and my partner weren't willing to wait that long," Mr Hunter said a few hours before the ceremony.

Australian Marriage Equality national convener Rodney Croome said the marriage of Mr Hunter and Mr Leith was tinged with sadness because their solemn vows would not be respected in Australian law.

"We call on the South Australian parliament to lead the nation toward marriage equality by allowing same-sex couples to legally marry and fully recognising same-sex marriages from overseas," he said.

"Reform at a federal level would be best, but in the absence of this, Ian Hunter's wedding is a strong impetus for South Australia to take the lead."

The SA parliament will consider a bill in 2013 to introduce same-sex marriage laws with MPs from both the Labor and Liberal parties to be granted a conscience vote.