The student group associated with Australia’s Liberal party has called for a free vote to be held on same-sex marriage, in spite of the party’s formal opposition.

The governing Liberal party has long opposed equal marriage, with Prime Minister Tony Abbott giving his backing to the successful fight to end the brief recognition of same-sex marriage in the Australian Capital Territory last year.

A vote on equal marriage was last held in the Australian Parliament in September 2012, when the House of Representatives rejected it by 98-42, with the Liberals whipped against, and the Labor party divided.

The Australian Liberal Students’ Federation passed a motion on Tuesday calling on the government to allow its MPs to vote freely on the issue.

ALSF Spokesperson Matthew Lesh said: “It’s pretty simple: two individuals who love each other should be free to marry.

“This does not impact other people’s lives, but does mean a lot to those same-sex-attracted individuals who are restricted from marriage.

“It is both liberal and conservative to support marriage equality. Liberals respect the rights of individuals to choose their own partners and their freedom to marry whom they decide.

“Conservatives recognise the importance of building a strong civil society by strengthening commitment between individuals regardless of sexual orientation.”

Abbott, who remains opposed to same-sex marriage, previously said the party would consider whether to whip MPs or not when a private member’s bill came before parliament.

He said: “Our policy has been that marriage is between a man and a woman, but in the end it’s up to the party room to decide what our policy is.”

Australian Marriage Equality national director, Rodney Croome, said: “The Liberal Students’ Federation has highlighted an important home truth to its seniors in the Coalition: marriage equality is about core the Liberal values of enhancing personal freedom and reinforcing family values.”

“The Federation’s support for marriage equality, and a free vote on the issue, is a reminder to Coalition MPs to live up to their own values.”

Despite close ties, the Australian Liberal Students’ Federation is not formally affiliated with the Liberal party.