Prime Minister Julia Gillard has rebuked one of her MPs after he called senior Liberal Julie Bishop "a narcissistic bimbo".
Just after 8am (AEDT) on Wednesday Victorian MP Steve Gibbons tweeted: "Libs are led by a gutless douchebag and a narcissistic bimbo who aren't fit to be MPs let alone PM and Deputy. Both should be sacked."
His tweet came as cabinet minister Craig Emerson was demanding Ms Bishop resign or be sacked for lying about how many times she'd spoken with notorious former union bagman Ralph Blewitt last week about the AWU slush fund scandal.
The tweet was quickly criticised by fellow Labor MPs and, later, by Ms Gillard.
A spokesman for the prime minister said she had "made clear to Mr Gibbons that his remarks were offensive and he has rightly apologised".
After a Twitter backlash, Mr Gibbons tweeted at 8.45am: "Apologies to those offended by my use of the word Bimbo. I'll replace that word with Fool."
An hour later he added: "To all of those offended by my Tweet posts this morning - I unreservedly apologise."
But the federal opposition is demanding more than a simple "sorry".
Status of women spokeswoman Michaelia Cash says the prime minister should force Mr Gibbons to stand down as deputy chair of a parliamentary committee.
"If Ms Gillard fails to take action immediately this will confirm that her statements in relation to misogyny and sexism are worth nothing and are part of a concerted campaign to undermine Tony Abbott," Senator Cash said in a statement.
"If the PM fails to take action this will expose the sheer hypocrisy and shameful double standards of the ALP."
Mr Gibbons, who has announced he is retiring from parliament at the next election, has a history of making colourful statements.
He called Kevin Rudd "a psychopath with a giant ego" during the former prime minister's leadership challenge in February.
Families Minister Jenny Macklin on Wednesday said the backbencher's language was clearly inappropriate.
"Nobody should use that language about other members of parliament," she told Sky News.
Sydney Labor MP Ed Husic said: "Steve, I love you, but you're way out of line."
Ms Bishop did not front the media on Wednesday but she did issue a statement which sought to clarify why she claimed on Tuesday that she'd only spoken with Mr Blewitt once.
What was Said
0810: Libs are led by a gutless douchebag and a narcissistic bimbo who aren't fit to be MP's let alone PM and Deputy. Both should be sacked.
0845: Apologies to those offended by my use of the word Bimbo. I'll replace that word with Fool.
0846: Libs are led by a gutless douchebag and a narcissistic fool who aren't fit to be MPs let alone PM and Deputy. Both should be sacked.
0953: To all of those offended by my Tweet posts this morning - I unreservedly apologise.