The WA Premier is heading to the polls in state elections on March 11, and is worried the plebiscite will be a distraction.
But the federal government says cabinet is yet to make a decision on the timing of a same-sex marriage vote.
The Australian Electoral Commission (AEC) has strongly recommended the federal government not hold a plebiscite on the topic before the end of 2016.
Prime Minister Malcolm Turnbull and senior ministers had previously repeatedly said they hoped to hold the vote this year (2016).
But Human Services Minister Alan Tudge told Sky News, 2017 is more likely.
"We're now getting advice from the Australian Electoral Commission to say that it's probably not practical to have it this year, so therefore it's likely to be next year."
Labor's Assistant Minister for Equality Terri Butler told Sky News it amounts to a broken promise.
"He went to the election telling everyone it would be done before the end of the year. If that wasn't true, why did he say it or did he just not know what he was talking about. He's weak, he's incompetent on this."
But Innovation Minister Greg Hunt says the time frame for a vote on marriage equality is yet to be determined.
