Australian laws stopping same-sex couples who married overseas from getting divorced violate international human rights obligations, the United Nations has found.
In a decision released overnight, the UN Human Rights Committee ruled an Australian woman has been denied equal protection of the law because Australia does not allow her to end a legal Canadian same-sex marriage.
"This decision is a timely reminder to the Australian government that banning same-sex couples from marriage is a breach of human rights," gay rights activist Rodney Croome said on Saturday.
The case was taken to the UN by Fiona Kumari Campbell, who married her ex-partner in Canada in 2004, before the couple separated later that year.
Dr Campbell wants to dissolve the marriage for personal and practical reasons, including having the option to remarry in the future and implications for overseas travel.
However, as same-sex marriage is not legal in Australia, Dr Campbell marriage is not officially recognised and therefore cannot be subject to divorce proceedings.
She cannot get divorced in Canada either, because she did not live there for at least a year.
The UN found the differential treatment Dr Campbell was subjected to regarding divorce proceedings was discriminatory.
"The UNHRC has recognised the unacceptability of differential treatment between different categories of foreign marriages," Dr Campbell said in a statement.
"This is another nail in the coffin of Australia's prohibition on marriage equality."
The decision comes as Liberal MPs prepare to plot a path forward on same-sex marriage during a special partyroom meeting on Monday.