Kevin Rudd will decide on Friday whether to challenge Prime Minister Julia Gillard for the leadership of Australia's ruling party as he lashed out at the tactics being used to discredit him.

The former leader, who quit as foreign minister while in Washington on Wednesday, arrived back in Australia a day after Gillard called a ballot for Monday to decide who should take the Labour party helm.

Rudd called a press conference at 0330 GMT to declare his hand as the venomous personal attacks on his character continued in what has become a deeply divisive rift that has plunged Labour into crisis.

Since he resigned as the country's top diplomat amid intense leadership speculation, Rudd, who remains popular with voters, has been savaged by senior cabinet ministers who accuse him of undermining the party for personal gain.

He hit back on Friday, telling people not to believe the scathing criticisms that suggested 'Kevin Rudd is the Antichrist incorporated, and if not the son of Satan, at least the grandson of Satan'.

"It's quite plain to me that what I see from the faceless men is the same shock and awe tactics that I seem to remember being deployed during the leadership coup during June 2010," he said on his arrival in Brisbane.

Gillard ousted Rudd as prime minister in a shock party-room coup in 2010 and Rudd has never forgiven his one-time deputy who now leads a minority government that relies on the support of independent and Greens MPs.

He urged voters to take matters into their own hands and 'pick up your telephone, speak to your local members of parliament, tell them what you think, jump into the media, tell them what you think'.

"The core question for members of the Australian parliamentary Labour party, for the Australian people, right now is whether they believe the current prime minister has the trust and confidence of the Australian people," he said.

"If you don't have that, you can't do anything else." Labour is badly lagging the conservative opposition ahead of elections due next year, with polls suggesting Gillard's administration would be dumped by the electorate if an election were held tomorrow.

Speaking shortly after Rudd's return, Gillard said the ballot was not a popularity contest but about who could govern best.

"It is a choice about who's got the strength, the temperament, the character, the courage, to lead this nation, who's got the ability to get things done even in the face of adversity," she said.

"This is not an episode of Celebrity Big Brother, this is about who should be prime minister."

On current numbers, Rudd is likely to lose and be banished to the backbench, according to media who have done a head count of the 103-member Labour caucus.

His other option is to vacate his seat, which would bring fragile Labour an unwelcome by-election in his Queensland precinct of Griffith.

Media said that at best he has the support of around a third of the Labour caucus -- well short of the clear majority needed to win.

So far, at least 20 ministers have publicly declared for Gillard with Attorney-General Nicola Roxon making clear Friday she could never work under Rudd again.

"He was very difficult to work with. There were a lot of challenges," she said, reinforcing characterisations that he was egotistical and controlling.

Rudd urged voters not to believe everything that was being said about him.

"Just have a little pause for thought. I may not quite be like that, there might be a vested interest at play in putting those views forward," he said.