Labor frontbencher Bill Shorten is set to announce his intention to stand as a candidate for the party leadership.
Mr Shorten is expected to hold a media conference in Melbourne later on Wednesday to say that he wants to lead Labor in opposition, a spokeswoman from his office told AAP.
He will be the first Labor MP to formally put his hand up for the job.
But he'll have to wait until Friday's ALP caucus meeting in Canberra to be formally nominated.
Fellow former minister Anthony Albanese is thought to be another likely contender for the job.