Businessman Clive Palmer today hit out at claims he has overstated his wealth and qualifications, and threatened to sue Rupert Murdoch while claiming the media magnate's former wife is a Chinese spy.

During an extraordinary round of breakfast television interviews, Mr Palmer threatened to sue Mr Murdoch over an opinion piece published today which questions his claims to being a billionaire, a mining magnate and a university professor, and says he paid to use titles including "president of the World Economic Forum" via large donations.

The article in The Australian newspaper, titled 'Why we need to worry about the real Clive Palmer', goes on to ask whether, given his record as a failed businessman, Australian voters should enable him to achieve "great political power".

According to latest polls, Mr Palmer's Palmer United Party (PUP) is on track to win the sixth Queensland Senate seat on Saturday.

Mr Palmer accused Mr Murdoch of telling his reporters what to write, likening the author of The Australian's article, award-winning investigative reporter Hedley Thomas, to "Black Caviar with a broken leg" and an apparatchik of News Corp.

"Murdoch will be sued by me today and will be brought to Australia to answer these questions in the Supreme Court," he told the Seven Network's Sunrise program.

"It's time this fellow was brought to account, this foreigner who tries to dictate what we do."

In a press release announcing his intention to sue Mr Murdoch, Mr Palmer said: "Mr Murdoch has sacked journalists and allowed his editors to turn their newspapers into propaganda sheets that Joseph Goebbels would be proud of."

When queried during his TV appearances over claims made in The Australian about his fortune and business dealings, Mr Palmer said he never claimed to be a mining magnate and did not know whether he was a billionaire.

"All I've said is I'm an Australian and I want to stand in the election," he said, adding: "I fear for Australia, with Kevin Rudd and Tony Abbott."

Deng had been 'spying on Murdoch'

Mr Palmer made his accusations regarding Mr Murdoch's estranged wife Wendi Deng on the Nine Network's Today show, saying: "She's been spying on Rupert for years, giving money back to Chinese intelligence... she was trained in southern China.

"Wendi Deng is a Chinese spy and that's why Rupert got rid of her."

He then added: "And this guy [Mr Murdoch] wants to control Australian politics. He wants to control what you think. Have a look at his newspapers."

Mr Palmer's defended the comments during a grilling on The World Today by Sabra Lane.

Sabra Lane: You've made unsubstantiated allegations this morning; you've accused Wendi Deng, the former wife of Rupert Murdoch, of being a spy. Where is your proof? Clive Palmer: Well, just go to Google and look it up on the US media and you'll see. Sabra Lane: Where is your proof? You have made these unsubstantiated allegations this morning. Where is the proof? Clive Palmer: Sorry, I'm trying to tell you, you poor woman, where it is. Go to Google, look it up, and you'll find all the proof on the US media where they're detailing ... what she's done."

The threat to sue Mr Murdoch comes less than 24 hours after Mr Palmer reportedly filed an $800,000 defamation suit against Liberal National Party candidate Mal Brough.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Listen Duration: 9 minutes 52 seconds 9 m Listen to Sabra Lane's interview Download 4.5 MB

According to The Australian, Mr Palmer's lawsuit claims that Mr Brough, a former Howard government minister, damaged his reputation by publicly refuting Mr Palmer's claims that he was approached to fund a sexual harassment case brought by James Ashby against his then-boss, former House Speaker Peter Slipper.

PUP will take 10 seats: Palmer

Mr Palmer predicts that his PUP will win 10 seats in Saturday's poll.

"We're looking for about 10 Senate seats across Australia. That's what our polling is telling us," he said on Sunrise.

"We're going to get a lot of Senate seats, we're going to get a lot of House of Representative seats, and we're going to change the country, mate," he told Today host Karl Stefanovic, adding that he should "vote for us and realise you're an Australian".

Mr Palmer dismissed criticism of an apparent request to employees via a company-wide email to volunteer at polling stations on Saturday.

Although he denied writing the email, Mr Palmer said he supported it.

"I think everyone who works with people, you want to support your colleagues," he said, adding that "it's a voluntary thing".

"[It's a] reflection of [their] commitment to the company and what we stand for."