Austria's Constitutional Court has decreed that same-sex couples will be allowed to marry by the beginning of 2019.

The move brings Austria into line with the likes of Ireland, Germany, France, the UK (excluding Northern Ireland) and Spain.

Same-sex couples in Austria have been allowed to enter legal partnerships since 2010, but until now it had not been legal to marriage.

The Constitutional Court examined a 2009 law following a complaint from two women who were refused permission to enter a formal marriage by authorities in Vienna.

It said in a ruling published on Tuesday that restrictions on same-sex marriage will be lifted at the end of 2018, unless the government does so itself earlier.

The Constitutional Court said that civil partnerships will remain an option after the law is changed, and will then be open to straight couples.

Austria is now the 16th European country to legalise same-sex unions.