Sydney, Jun 20 (IANS): Australian Prime Minister Malcolm Turnbull on Monday promised a referendum on legalisation of same-sex marriages before the year ends, if he is re-elected.

"Of course, if we are successful on July 2, then I have every expectation that the parliament will swiftly legislate for a plebiscite and a plebiscite will be held shortly after parliament resumes, which I would assume to be in August," Turnbull said during an event in Sydney.

"So I would hope that the plebiscite could be held before the end of the year," said Turnbull.

Opposition Labour Party leader Bill Shorten asked Turnbull to legalise same-sex marriage immediately instead of calling a referendum, which he said, will become a "platform for homophobia".

"I intend to win the election. I intend to put forward legislation in the first 100 days," Shorten said.

Australia, which accepts civil marriage in several of its states, has been criticised for failing to legalise same-sex marriages.

In December 2013, the High Court overturned a law allowing gay marriages in the Australian Capital Territory on grounds that it contravened the Federal Marriage Law of 1961.

Similar legislative proposals have also failed in the states of Tasmania and New South Wales.