PM to miss Thomson's speech to parliament

Suspended Labor MP Craig Thomson is set to tell federal parliament on Monday he never used union funds to pay for prostitutes.

Suspended Labor MP Craig Thomson is set to tell federal parliament he never used union funds to pay for prostitutes, but Prime Minister Julia Gillard probably won't hear his much-anticipated explanation.

The PM is in Chicago for a major NATO summit and has suggested she won't be watching when Mr Thomson rises to his feet around midday on Monday - which will be late Sunday evening in the United States.

"Look, I'll be focused on the work here at the summit," Ms Gillard said when asked if she'd be tuning in to the lower house.

Nevertheless, most eyes will be on the former Health Services Union (HSU) boss when he attempts to explain how Fair Work Australia (FWA) found he spent $500,000 of union funds on escort services and personal and election campaign expenses.

The NSW member for Dobell has received plenty of advice regarding what not to say during his 30-minute speech.

Shadow attorney-general George Brandis warned Mr Thomson not to make matters worse by being loose with the truth.

"I would counsel him that misleading the parliament is itself a serious breach of the privilege of the parliament," Senator Brandis told Network Ten on Sunday.

"What Mr Thomson ought to do is tell the truth."

Senator Brandis said Mr Thomson's TV interview last weekend, during which he again denied any wrongdoing, was different from the explanation he gave on radio in August 2011.

"If you told one version of events last year, and you've given a different version of events more recently, then one doubts the credibility of the witness concerned," he said.

Mr Thomson is expected to maintain his innocence on Monday and attack FWA for denying him natural justice and conducting a shoddy investigation.

He could also name HSU officials who he says set him up with records of escort services to damage his political prospects.

Mr Thomson will tell parliament he didn't use his union credit card to pay for prostitutes, that his signature was forged and his driver's licence number was used by someone else.

He told the Nine Network last weekend that "proof of a phone call is not proof of who's on the end of the phone".

Another politician giving out free advice on Sunday was independent senator Nick Xenophon.

He too wants the truth and nothing but the truth.

"If his account is found down the track not to be truthful, not to be accurate, to have misled parliament in any way, then that would trigger a privileges inquiry," Senator Xenophon told Sky News.

"And the consequences of that could be a suspension."

Even if Mr Thomson was only turfed out for a few weeks it could have enormous political consequences, given the tight numbers in the house. Opposition Leader Tony Abbott has threatened to test the crossbench's support for Labor by bringing on a no-confidence motion.

Mr Thomson could also face a referral to the parliament's privileges committee this week over his late reporting on the members' interest register of legal expenses paid to him by the NSW ALP.

Senior minister Craig Emerson said on Sunday that "Mr Abbott will seek to do whatever he can to change the balance of power in the House of Representatives".