A senator has been accused of making derogatory growling noises as Jacqui Lambie was speaking in parliament hours after the release of a damning report into the building’s workplace culture.
Liberal Senator David Van has since apologised "unreservedly" for interjecting as Senator Lambie spoke but said he does not "accept the characterisation" of his remarks.
Greens Senator Sarah Hanson-Young and Labor’s Senate Leader Penny Wong had earlier both testified to hearing the noises as Senator Lambie asked a question in the Senate.
Senator Hanson-Young rose quickly to her feet after Senator Lambie had finished speaking to raise her concern about the alleged incident.
She said it was not appropriate for the noises to be made, especially as a female member was speaking.
“I don’t think it’s appropriate given what has been handed down today to have growling noises coming from [that] side of the chamber - while a female member in this place is on her feet,” she said.
“It happened. I don't know who is responsible for it but it's inappropriate and if we are going to change the culture from the top that means all of us.”
Senator Wong said she had also heard the noise and asked for the remarks to be withdrawn - but no senator claimed responsibility.
"At least 'fess up," she said.
"Gee you're tough aren't you? You're happy to dish it out, but not happy to take responsibility - I mean really, growling."
Senate President Slade Brockman said he did not hear the alleged incident and so could not make a ruling or force any senator to withdraw the remarks.
“If it occurred I would ask the Senator involved to reflect upon it and to withdraw if they did do what has been stated,” he told the Senate.
Senator Van later fronted the Senate chamber to apologise for "making interjections" while Senator Lambie was speaking.
"While I do not accept the characterisations of my interjections in the manner that was raised in points of order at that time by other Senators, I do regret the interjections and I apologise to Senator Lambie and to the Senate unreservedly," he said.
Senator Lambie had been asking Leader of the Government in the Senate Simon Birmingham about what she described as a lack of social housing.

Liberal Senator David Van. Source: AAP
Senator Birmingham said the conduct was "unacceptable" when questioned about the alleged incident and he had asked the government whip to try to determine who made the noises.
"If it occurred they ought to apologise," Senator Birmingham told the ABC.
"There is a standard of conduct everyone (in parliament) should adhere to."
With AAP