Gay marriage first ALP law after election

If elected prime minister on Saturday, Bill Shorten will make legalising gay marriage his first legislative priority.

Bill Shorten has vowed to make same-sex marriage laws the first piece of legislation a Labor government puts to parliament.

It's a step up from the opposition leader's previous promise to legislate within 100 days of winning power.

"No $160 million plebiscite, no hurtful, hateful government-sponsored advertising campaign for us," he told the National Press Club on Tuesday.