Factbox: State of same-sex marriage around the world

Australia on Thursday became the 26th nation to legalise same-sex marriage, following a postal survey in which Australians overwhelmingly voted in support of formalising the unions.

The laws, which will also recognise same-sex marriages carried out in foreign countries, take effect from Saturday. Because a month's notice is required for the state to recognise a marriage, the first legal same-sex unions will be in January.

Lawmakers, who had cast aside a conservative push to allow religious objectors to refuse service to same-sex couples, waved rainbow flags and embraced in parliament, where earlier in the debate a politician had proposed to his same-sex partner.

Here are some facts about same-sex marriage around the world:

* Same-sex marriage is legal in 26 nations: Argentina, Australia, Belgium, Brazil, Britain, Canada, Colombia, Denmark, Finland, France, Germany, Greenland, Iceland, Ireland, Luxembourg, Malta, Mexico, Netherlands, New Zealand, Norway, Portugal, South Africa, Spain, Sweden, Uruguay, United States.

*It is also set to become legal soon in Austria and Taiwan, following court rulings on the matter this year.

Australia parliament members celebrate before the passing of the Marriage Amendment Bill in the House of Representatives at Parliament House in Canberra Dec 7, 2017. AAP via Reuters

* In some of these countries, such as Mexico and Britain, marriage is only open to same-sex couples in some regions. Northern Ireland is the only part of the United Kingdom where same-sex marriage is not allowed.

* The first country to legalise same-sex marriage was the Netherlands in 2001.

* Some Australian states ruled homosexual acts to be illegal until just 20 years ago.

* In Africa, where homosexuality is a crime in many countries and can lead to imprisonment or the death penalty, South Africa alone has granted the same access to gay couples. Same-sex marriage legislation came into force there in 2006.

* No countries in Asia allow same-sex couples to marry or enter civil unions of any kind. In May, Taiwan's constitutional court ruled that same-sex couples have the right to legally marry, the first such ruling in Asia.

* Almost one in three adults globally believe people of the same sex should be allowed to marry, a survey of almost 100,000 people in 65 countries showed in 2016.

Sources: International Lesbian, Gay, Bisexual, Trans and Intersex Association or ILGA, Pew Research Center, Reuters.