By chief political correspondent Simon Cullen
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Senior Coalition MPs have launched a coordinated attack on Peter Slipper, saying his position as parliamentary Speaker is now "untenable" and Labor should dump him.
Copies of text messages sent by Mr Slipper to his stood-aside staffer James Ashby have been tendered to the Federal Court as part of a sexual harassment case.
They show Mr Slipper used lurid language to describe female genitalia.
Deputy Liberal leader Julie Bishop has seized on the revelations, demanding Labor take action against Mr Slipper given its swift condemnation of sexist remarks directed at the Prime Minister.
"I believe Mr Slipper's position as Speaker is untenable," Ms Bishop told ABC Radio National.
"He has made deeply offensive remarks about women, including women in the Parliament.
"If the Government is genuinely concerned about what it terms sexist and misogynist behaviour, then there is a serious test ahead for the Prime Minister.
"The Prime Minister must state whether she continues to support a person in the position of Speaker who makes disgusting and offensive remarks about women."
Labor has regularly suggested Opposition Leader Tony Abbott has a problem with women, and has sought to blame him for a culture of aggressive attacks directed towards Julia Gillard.
The Coalition says Labor now has no choice but to dump Mr Slipper from the Speaker's role.
A string of senior Coalition MPs, including Mr Abbott, have fronted the media this morning to describe Mr Slipper's position as "untenable".
"We're increasingly aware of his attitude towards women, and obviously we're aware of some of the absolutely gross descriptions and the foul language that this particular individual seems habituated to," Mr Abbott told reporters.
"I think the Speaker's position has become absolutely untenable."
Muted response
Ms Gillard this morning attended a Breakfast with Powerful Women event in Canberra and has not yet commented on the text messages.
Labor's response has been muted because it argues that it would be inappropriate to comment on a matter before the court.
Assistant Treasurer David Bradbury has described the text messages as "comments that I would not consider acceptable".
"As to whether they have actually been made, that will be a matter for the courts," he said.
"Mr Slipper's position remains as it is until such time as those matters are determined before the courts - that has not yet occurred."
Liberal frontbencher Sophie Mirabella, who was the subject of another of Mr Slipper's text messages, says she was "shocked" by the language used by the stood-aside Speaker.
Independent MP Andrew Wilkie has described the issues surrounding Mr Slipper as a "high farce" that needs to be fixed.
"Either Peter Slipper needs to have the good sense to resign the Speakership and sit on the cross-bench until all criminal and civil allegations against him have been dealt with, or the Prime Minister and Opposition Leader need to put aside their political differences and have the Parliament elect a new Speaker."
Fellow independent MP Tony Windsor says he plans to speak with Mr Slipper this week about the veracity of the text messages.
He says if they are true, it would raise questions about his capacity to return to the Speaker's position.
Meanwhile, papers released by the Federal Court suggest Mr Slipper's former staffer James Ashby has symptoms of anxiety and depression caused by his former boss.
