A Labour MP has apologised for using "offensive and unacceptable" language at the party conference last month.
Norwich South MP Clive Lewis was filmed on stage at a fringe event in Brighton saying: "Get on your knees, bitch" - the video emerged on social media.
Among female MPs criticising him was Labour's Harriet Harman, who tweeted: "Inexplicable. Inexcusable. Dismayed."
The Labour Party said the language "was completely unacceptable and falls far short of the standard we expect".
It is not clear who Mr Lewis, a former frontbencher, was addressing in the video. He is among several people on stage at the time.
Aaron Bastani, the co-founder of left wing website Novara Media, tweeted: "I was there. The video has been up at @novaramedia for a month - Clive was saying this to a man."
But after criticism of his alleged comments, Mr Lewis tweeted: "I apologise unreservedly for the language I used at an event in Brighton last month. It was offensive and unacceptable."
Among MPs lining up to condemn his language on Twitter were the Conservative Mims Davies, who suggested Mr Lewis needed to go on a training course.
Mr Lewis's fellow Labour MP Jess Phillips said: "Just seen the Clive Lewis video. Obviously I am appalled, just listened to seven teenage girls speak up about gender inequality. Perhaps I'll bring them to work on Monday."
And Rebecca Hilsenrath, chief executive of the Equality and Human Rights Commission, said Mr Lewis's use of language was "completely inexcusable" adding: "We, and the women in Mr Lewis's constituency, have every right to expect our MPs to behave in a more professional manner."
Education Secretary Justine Greening, who is also minister for women and equalities, called on Jeremy Corbyn to help stamp out misogynistic behaviour towards MPs.
The Conservative minister said the Labour leader should condemn Mr Lewis's words and asked Mr Corbyn to set out how he was going to stamp out sexism in his own party.
BBC East political correspondent Andrew Sinclair said the MP has told friends the comments were directed at a man during a "boozy and sweary" comedy event as part of "on-stage banter" and were not intended to cause offence.
But, he added Mr Lewis accepts he should not have said it and was full of remorse.
Chloe Smith, Conservative MP for Norwich North, said the Labour leader Jeremy Corbyn should "seriously consider" withdrawing the whip from Mr Lewis.