The Minister Against Women

Wilcox Cartoon

Labor has demanded a formal apology from cabinet minister Michaelia Cash after she withdrew an extraordinary threat to make public "rumours" involving female staffers in Bill Shorten's office.

Senator Cash backed down from the threat on Wednesday after the opposition pressured her to withdraw the "disgraceful" outburst made during a parliamentary inquiry.

The jobs minister reacted angrily when Labor frontbencher Doug Cameron asked if her newly appointed chief-of-staff, who is yet to start work, was formerly employed in another Liberal office.

"If you want to start discussing staff matters be very, very careful because I'm happy to sit here and name every young woman in Mr Shorten's office over which rumours in this place abound," Senator Cash told the Senate hearing under parliamentary privilege on Wednesday.

"Do you want to start naming them? Do you want [me] to start naming them for Mr Shorten to deny any of the rumours that have been circulating in this building now for many, many years?"

Deputy Labor leader Tanya Plibersek called on Prime Minister Malcolm Turnbull to ask the WA senator for a proper apology, rather than her "mealy-mouthed weasel" retraction.

"Senator Cash's comments where ghastly, they were sexist, they were a 1950s style throwback," Ms Plibersek told parliament.

Labor's Senate leader Penny Wong earlier told the Senate hearing the minister had made "outrageous slurs" against female staff working in the opposition leader's office.

"It can't be allowed to stand. I think it is disgraceful and sexist and it is impugning of the character of various staff. I would ask the minister to withdraw," Senator Wong said.

Senator Cash in "Brain Snap" mode