Julia Gillard has repeatedly referred to the "strong support" of her colleagues but sidestepped questions about whether she should sack Kevin Rudd or bring on a leadership spill.

Earlier today, Labor heavyweight Simon Crean launched a blistering attack on Mr Rudd, calling on Ms Gillard to summon him for a "frank" discussion and, if need be, sack him for disloyalty.

Leadership tensions have reached fever pitch since the weekend with several backbenchers and cabinet ministers publicly voicing their backing for either the Prime Minister or Mr Rudd.

The ABC has been told by supporters on both sides that the row could be resolved as early as next week when Parliament resumes.

At a press conference to release the Gonski review of schools funding, Ms Gillard was peppered with questions about the leadership but gave no indication about her plans regarding Mr Rudd.

"As Prime Minister, each and every day I work with my caucus colleagues and am thankful to them for their very strong continuing support," she said.

"I'm getting on with the job with the strong support of my caucus colleagues. Kevin Rudd is overseas getting on with his job too as Minister for Foreign Affairs.

"I understand (the media) is interested in other things, but my focus is on doing what I need to do today as Prime Minister to set us up to be the nation we want to be in the future."

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Mr Rudd is out of the country on a one-week, five-nation trip and is not due to return to Australia until the weekend.

Mr Crean, himself a former Labor leader, says independent MP Andrew Wilkie's assertion over the weekend that he had spoken about the leadership with Mr Rudd in November made it clear that he had been "disloyal internally".

"I know that he has been talking to other people," Mr Crean told ABC Local Radio in Melbourne this morning

"Do you need the evidence?

"I think you need to have that conversation and it needs to be a frank one, and it needs to be an assertion of leadership by the Prime Minister, and then we get on with the task."

He says it is a "question of judgment for her" as to whether Ms Gillard sacks Mr Rudd after their conversation.

That could lead Mr Rudd to resign from his Brisbane seat and trigger a by-election - something the minority Labor government has been desperate to avoid.

"No loyal person would knowingly put the party in that position if it had the potential to further destabilise government," Mr Crean said.

Sorry, this video has expired Labor leadership row reaches boiling point (Photo: AAP/ Penny Bradfield)

A spokeswoman for Mr Rudd said he and Mr Wilkie did meet late last year but said Mr Wilkie raised the leadership issue "late in the conversation".

"At no point did Mr Rudd indicate he was seeking the leadership nor request support for it," the spokeswoman said.

Mr Wilkie released a statement this afternoon agreeing with Mr Rudd's account.

"Mr Rudd and I discussed the leadership in generalities only," he said.

"At no stage did Mr Rudd ask for my support on the floor of the Parliament or did I offer my support. Nor did Mr Rudd take the opportunity to criticise the Prime Minister."

However, the key independent MP has reiterated his preference for the former Labor leader.

"I would find it easier to work with Kevin Rudd than Julia Gillard, considering how she reneged on her written agreement with me and the fact she hasn't spoken with me for the month since I withdrew my support from her government," he said.

When asked whether that conversation and numerous reports that he had briefed journalists on his comeback plans constituted disloyalty by Mr Rudd, the Prime Minister would only refer to his public denials.

"On the question of the conversation with Mr Wilkie, the Minister for Foreign Affairs has denied that version of events," she said.

"On the question of journalists and background breifings, it's been reported that the Minister for Foreign Affairs has denied that too."

Factional powerbrokers have told the ABC the leadership issue must be brought to a head.

Predictions of how much caucus support Mr Rudd holds vary, but it is widely estimated that around one third of the 103 MPs and Senators support him.

Another third back the Prime Minister and the rest are undecided.

Mr Crean says Mr Rudd should "put up or shut up" and has advised Ms Gillard not to call for a spill.

"Kevin hasn't got the numbers to challenge," he told ABC Local Radio.

"He's well short of anywhere near a majority. He can't win.

"If he can't be part of the team then he should exit the team or challenge."

Sorry, this video has expired Andrew Wilkie discusses the Labor leadership

Mr Crean says the team wants "the end of the madness".

He is the latest, and most strident, in a string of cabinet ministers to voice their support for the Prime Minister and criticise the man she ousted.

Gillard loyalist and Trade Minister Craig Emerson has urged an end to the destabilisation.

"There is a campaign on here and it's a campaign that is anti-Labor, it's against the interests of the Government of Australia and it's against the national interest and it should stop... and it is being run by Labor people which is quite appalling, absolutely appalling and I think people are sickened by it, " he told ABC NewsRadio.

Defence Minister Stephen Smith, who has been reported to have concerns about Ms Gillard's leadership, has issued a statement to clarify his support for her.

"I strongly support the Prime Minister," he said.

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"I think the Prime Minister is doing a very good job in tough circumstances."

Arriving in Canberra for this afternoon's Cabinet meeting, several ministers would only reiterate that Ms Gillard had their full support.

Attorney-General Nicola Roxon said ministers were getting on with the job of governing.

"I'm here to get on with the business of government... that's what we should be allowed to get on with doing and that includes Julia being allowed to get on with being Prime Minister," she said.

Some of the more vicious criticism of Mr Rudd came from Labor backbencher Steve Gibbons.

Yesterday he released statements via Twitter and on his website calling Mr Rudd a "psychopath with a giant ego" and saying he had a "chaotic and deeply offensive style of leadership".

This morning he told ABC Local Radio that he did not "run away" from his comments.

"The Rudd forces, if you like, have been gradually building momentum and carrying out what I regard as a very destructive destabilising campaign," he said.

"The idea was to stop the momentum being built up by the Rudd forces to continue the destabilisation by pointing out a few home truths."

Opposition Leader Tony Abbott called the Labor party "hopelessly divided" and repeated his call for a new election.

"There's the Gillard party, there's the Rudd party and there's the neither party and that's just not going to provide us with the kind of leadership we need," he said.

"I think we need change of policies and the only way to get change of policies I think is to have a change of government at an election."