Liberal frontbencher Michaelia Cash has been forced to back down from a threat to reveal the names of “young women” working in Bill Shorten’s office who she claimed were the subject of “rumours”.

Senator Cash made the threat during Senate Estimates on Wednesday morning as Labor’s Doug Cameron grilled her about members of her own staff.

“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,” she told the hearing.

“Do you want to start naming them and for Mr Shorten to come out and deny any of the rumours that have been circulating in this building now for many, many years.

“It’s a dangerous path to go down.”

It comes only a few days after the identity of a Western Australian woman who had lodged a sexual harassment complaint about former deputy prime minister Barnaby Joyce was leaked to the media, and two weeks after Malcolm Turnbull railed against sexist culture in Canberra.

Senator Cameron described the threat as “nonsense” and told Senator Cash to “take a chill pill”.

But after Senator Cash repeated she was happy to put those names on the record, Labor’s Senate Leader Penny Wong entered the hearing, labelled the comments an “outrageous slur”, and demanded she apologise.

“It can’t be allowed to stand. It’s disgraceful and it’s sexist. And it is impugning of the character of various staff,” she said.

Senator Cash, the Minister for Jobs and Innovation, initially declined to withdraw the threat, saying: “I do not agree with your summation of what was said.

“Senator Cameron was clearly maligning my staff,” she said.

“The point I was making was rumours circulate in this place. It does not mean they are true.”

Senator Wong threatened to raise the issue in the Senate if she did not withdraw.

“If anyone has been offended by my remarks, I withdraw,” Senator Cash replied.

The New Daily contacted Mr Shorten’s office, which referred to Senator Wong’s remarks and noted Senator Cash had apologised.

There has been an unprecedented focus on the sex lives of politicians after it emerged this month former Mr Joyce had an affair with his former media adviser Vikki Campion.

That focus was fuelled by Mr Turnbull’s decision to ban sex between ministers in their staff, and to suggest there was a culture problem at Parliament House.

At an extraordinary press conference, he emphasised there was a “gender perspective” to the Joyce scandal and the culture at Parliament House more broadly, saying: “I think many women in this building … understand very powerfully what I am saying.”

He said he was updating ministerial standards to ensure Parliament was a workplace “where women are respected”.

In a speech before Question Time, Labor deputy leader Tanya Plibersek demanded Senator Cash offer a “proper apology”.

“Today the Minister for Jobs, attacked young women doing their jobs,” she said.

Senator Cash is a former Minister For Women, and represents the current Minister Kelly O’Dwyer in that portfolio in the Senate.

At the hearing on Wednesday, Senator Cash objected to Senator Cameron’s close scrutiny of those now working in her office.

He had asked Senator Cash for the name of her chief of staff, but coalition members of the committee arguing naming individual advisers was against convention.

Last year, Senator Cash’s media adviser David De Garis resigned from his job after admitting he had tipped off the media about a police raid on the Australian Workers Union’s offices.

Senator Cash had initially told a Senate estimates hearing her office had not told the media about the raises, but was forced to correct her evidence when it was contradicted by a Buzzfeed report.