Gay marriage vote might 2016: senator

A prominent backer of same-sex marriage legislation has warned advocates that a parliamentary vote may not take place this year.

However, Liberal Democrat David Leyonhjelm says he is reasonably confident a bill co-sponsored by himself, the coalition, Labor and the Greens will win the support of parliament.

"I wouldn't be surprised if it gets held over until the first half of next year," he told Sky News on Tuesday, adding it would be "done and dusted" by June.