Peter Dutton has backed embattled Defence Minister Linda Reynolds who has faced intense criticism after calling an alleged rape victim a “lying cow”.

Former Liberal staffer Brittany Higgins alleges she was sexually assaulted by a fellow ministerial adviser in Senator Reynolds’ office in 2019.

The Home Affairs Minister rejected fresh calls for Senator Reynolds to quit over the remark, which was made in front of several staff in her office last month.

“(Scott Morrison) was rightly strong in his rebuke of Linda for using those words and she’s apologised for that,” Mr Dutton told the Nine Network on Friday.

“Linda genuinely felt hurt by the fact she thought she had provided every assistance possible obviously over a period of time.”

He said Senator Reynolds wasn’t questioning the veracity of the rape allegations, but responding to suggestions she hadn’t supported ex-staffer Ms Higgins.

The minister is facing defamation action unless she apologises to Ms Higgins, who says the comment was incredibly hurtful.

“I appreciate that it has been a stressful time but that sort of behaviour and language is never excusable,” Ms Higgins said in a statement.

“It’s just further evidence of the toxic workplace culture that occurs behind closed doors in Parliament House.”

Mr Dutton said the Prime Minister was right to rebuke the Defence Minister but she did not need to resign.

“I see Linda in action around the national security committee of cabinet, she is incredibly competent,” he said.

Peter Dutton does not believe Linda Reynolds should stand down. Photo: AAP

Deputy Labor leader Richard Marles urged the minister, who said sorry to the staff that heard the remark, to apologise directly to Ms Higgins.

“The Prime Minister himself should be making an apology to Brittany Higgins,” he told Nine.

“He ducks at every moment and Linda Reynolds is under pressure because basically, the Prime Minister has hung her out to dry.”

Independent senator Jacqui Lambie said the leaks from Senator Reynolds’ office showed the minister must relinquish the defence portfolio.

“When you’ve lost the respect of your own people and they’re going out to the media, I think you’re gone,” she told ABC radio.

She said the sexual assault allegations engulfing federal Parliament had further eroded public trust in politics.

“It nearly brings tears to my eyes that people are saying ‘what is going on here?’,” Senator Lambie said.

“It is absolutely disgraceful.”

Senator Reynolds is on medical leave after her cardiologist recommended time off when she was under immense pressure over her handling of Ms Higgins’ complaint.

-with AAP