The High Court has ruled the government's postal survey on same-sex marriage can proceed

The High Court has ruled the government's postal survey on same-sex marriage can proceed.Marrige equality advocates had argued the Turnbull government should not have bypassed parliament in funding it.

A mural in Webb St in the inner-city Melbourne suburb of Fitzroy Source: AAP

The government found the $122 million by using laws to make an advance payment to the finance minister in circumstances where there is an urgent need for spending and the situation was unforeseen.

The ruling means the Coalition will hold a free vote in parliament on the subject if a majority of Australians vote in favour of legalising same-sex marriage.

Forms are expected to be delivered to Australian households by September 25th. Marriage equality advocates want to stop the government's upcoming postal survey because its funding hasn't been approved by parliament.

In Question Time, Prime Minister Malcolm Turnbull welcomed the court decision. After that the federal opposition has invited the Prime Minister to campaign on behalf of the Yes vote.