Former deputy Liberal leader Julie Bishop says women need to take up 50 per cent of federal parliamentary seats before there will be an end to the toxic misogyny she saw during her 20-year political career.

With more women representatives, bad behaviour and misogyny would be called out, Ms Bishop – who retired from politics at the 2018 election – told Andrew Denton on Seven’s Interview program on Tuesday night.

She described as “grotesque in its brutality” and “pathetic” the sexualisation of Australia’s first female prime minister, Julia Gillard, during a 2013 Liberal Nationals party fund-raising dinner in Queensland.

The former WA representative blamed her male colleagues for creating a culture that allowed a quail dish to be likened to the Labor leader as having “small breasts, huge thighs and a big red box”, The Daily Telegraph reports on Wednesday.

“We have to remember that in recent times, parliament was all male. And so you had a whole bunch of men in Canberra and they set the rules, they set the customs, the precedence and the environment. It was all men,” Ms Bishop said.

“There was very much that culture around politics, even though [Australians] were world-leading as the first to simultaneously grant women the right to vote and the right to stand for parliament … but that kind of behaviour’s just pathetic,” she said.

TOMORROW: "I love men and I think they have a wonderful contribution to make to humanity. But if you’re the only female voice in a room, they just don’t seem to hear you." – @HonJulieBishop on often being the only female in a room of men. #InterviewAU 8.30pm Tues on @Channel7. pic.twitter.com/PsbgmvfGjH

— Andrew Denton's "Interview" (@InterviewAU) August 12, 2019

Ms Bishop said only with more female representatives would such misogyny and bad behaviour be called out.

“There must be a critical mass of women, and 50 per cent sounds like a good idea,” she said.

“I would think that the more women that are in politics, the more they would say that behaviour is unacceptable. So I think the numbers really do matter in this instance.”

In a wide-ranging interview, Ms Bishop also explained her failed bid for the Liberal leadership after the infamous coup of 2018, saying she felt an “overwhelming responsibility” to stand.

“I also felt that I owed it to the women of Australia because I’d been the deputy and, you know, criticised, “oh she’s always the bridesmaid’,” she said.

“I didn’t want them to think ‘oh, she hasn’t got the courage to stand even though she might lose’.”

In what became a three-cornered contest – between Ms Bishop, Home Affairs Minister Peter Dutton and now Prime Minister Scott Morrison – the former deputy leader got only 11 votes.

“I was the last into the race,” she said.

“I waited until Malcolm [Turnbull] had actually announced that he wasn’t going to contest. Whereas others didn’t.”

Ms Bishop said she found it “disturbing” to be the only female minister in Tony Abbott’s 2013 cabinet, describing it as “gender deafness”.

“I love men, and I think they have a wonderful contribution to make to humanity, but if you’re the only female voice in the room they just don’t seem to hear you,” she said.

Ms Bishop retired from politics at the May election. She has since been announced as the next chancellor of the Australian National University, and has also joined the board of Palladium, a move that brought a review by the Prime Minister’s Department amid claims it breached ministerial standards.

-with AAP