Cabinet minister and Labor factional leader Bill Shorten says he does not believe there will be a leadership ballot next week, as a key supporter of the Prime Minister challenges Kevin Rudd to "put up or shut up".

It is expected the leadership impasse will be broken late next week, as parliamentary sittings wind up for the final time before the September 14 election.

Angered by the ongoing leadership talk, one of Julia Gillard's key Cabinet supporters, Resources Minister Gary Gray, has challenged Mr Rudd to test his support in Caucus.

Mr Shorten, who is widely believed to be the critical "turnkey" in the leadership stand-off, also repeatedly sidestepped questions about whether he would continue to support the Prime Minister until the next election.

However, when peppered with questions about the leadership this morning on Fairfax radio, Mr Shorten would only wearily reply "no" there would not be a ballot next week or indeed before the election, and "no" he would not be reviewing his support for Ms Gillard.

"The leadership debate comes up in the context that Labor's doing it hard at the moment in the polls," he said.

"People want to make sure - Labor voters want to make sure - that Labor's as competitive as can be at the election."

Key points: Bill Shorten says he dos not believe a leadership challenge will take place but avoids questions about his support for Julia Gillard

Bill Shorten says he dos not believe a leadership challenge will take place but avoids questions about his support for Julia Gillard Kevin Rudd says he doesn't believe there are any circumstances under which he would return to the Labor leadership

Kevin Rudd says he doesn't believe there are any circumstances under which he would return to the Labor leadership Mr Rudd's comments come after Labor MPs, including his own backers, rally behind Ms Gillard

Mr Rudd's comments come after Labor MPs, including his own backers, rally behind Ms Gillard It is expected the leadership impasse will be broken late next week

He was asked half a dozen times whether he would continue to support Ms Gillard until the next election and repeatedly answered: "I continue to support our Prime Minister, full stop."

He eventually pledged his support into the future, saying: "I will continue to support our Prime Minister, yes."

Mr Rudd says the country has "just had a gutful" of the speculation.

However, he has been accused of using "weasel words" when answering questions about whether he would launch a leadership challenge.

"I don't believe there are any circumstances under which that'd happen," he told Channel Seven this morning.

'Put up or shut up', Gray tells Rudd supporters

Mr Gray, a former ALP national secretary, has hit out at Mr Rudd and his supporters and challenged them to test his numbers in Caucus.

"I do believe they should put up or shut up," he told The World Today.

Mr Gray says the former prime minister's language is "confusing and I think Kevin is confused".

"I genuinely think that if Kevin wishes to challenge, he should do so. He should stop this confusion and the mumbling and the mumbo jumbo," he said.

"He should test his level of support or he should get on with the campaign to ensure Labor's vote is as strong as it can be and to ensure that Labor wins the election."

Mr Rudd has taken advantage of the "long shadow" he casts in the media, according to Mr Gray, and created a damaging "diversion".

"What Kevin does is he draws the conversation so it's the Labor party talking about itself and that is such an unproductive activity," he said.

"It deliberately undermines the political platform the Prime Minister has created in education, in disabilities reform, in training and in jobs and in ensuring the economic management of our country is as good as it can be."

Mr Gray went on to say that Mr Rudd's supporters "need to get on board".

"We all need to respect the political and public policy reality that politicians talking about themselves, and about their own personal ambitions is only destructive and it's reminiscent of a party divided," he said.

"A house divided cannot stand and therefore all members of the parliamentary Labor party need to be cognisant of the real challenges that we face as we go through the last week of this sitting."

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 7 minutes 44 seconds 7 m Gillard ally Craig Emerson tells 7.30 the leadership tussle is over

Rudd backer and western Sydney MP Ed Husic has retaliated by accusing Mr Gray of fuelling the internal fight.

"I thought those words were pretty provocative, and instead of trying to trigger a blue he should be triggering a turnaround," he told Sky TV.

"We are basically stuck in a rut and we need to find a way to get out."

Another Labor powerbroker has backed Ms Gillard, saying there will be no change to the Labor leadership.

Labor's national vice president and the national secretary of the Transport Workers Union, Tony Sheldon, told AM that Ms Gillard has his 100 per cent support because her Government secured greater protection for the trucking industry.

"There's a very clear course of action. We either support the people who have made a difference for the people in the trucking industry - they've taken on the most powerful people in the country, or we listen to some polling which will switch once the media starts after Kevin Rudd," he said.

"People should be getting behind the Gillard Government for what historical changes they've made on behalf of the Australian public. When it comes to Kevin Rudd we all know what will happen the following day if Kevin Rudd was there."

But Liberal frontbencher Christopher Pyne told reporters last night that anyone pretending to know what is going on in the Labor Party at the moment is "having a lend of themselves and the general public".

Parliament resumes for the last sitting week on Monday.

Ms Gillard will then travel to Indonesia for talks with president Susilo Bambang Yudhoyono on asylum seekers - a key issue for Labor in the lead-up to the election.