Labour leader, Jeremy Corbyn, has denied the party was slow to deal with Sheffield MP, Jared O'Mara, over claims about his use of offensive language.
Appearing on an LBC radio programme guest-hosted by London mayor Sadiq Khan, Mr Corbyn insisted that Labour took the matter seriously after suspending the Sheffield Hallam MP while allegations against him were investigated.
Mr Corbyn said: "The issue came to light last weekend. It was discussed at the Parliamentary Labour Party on Monday. The later revelations appeared the following day. He was suspended on Wednesday morning."
Mr O'Mara is the subject of a Labour inquiry over claims that he called a constituent an "ugly bitch" earlier this year, an allegation he denies.
However, the decision to suspend Mr O'Mara the whip followed further claims about his online comments, including a reference to actress Angelina Jolie performing oral sex.
Mr Corbyn said: "Anybody making abusive comments anywhere is unacceptable, completely wrong, and has to be challenged and dealt with.
"It became apparent that there was stuff on the internet from Jared O'Mara that was, actually, some of it, was quite old, the early 2000s, and this came to light.
"He then discussed it, and made a very, very full apology to the Parliamentary Labour Party on Monday night which was, actually, quite well received.
"After that it became apparent that there was also stuff on the internet from much later on than that. And, on the basis of that, we thought the right thing to do was to suspend his membership of the party, and thus of the Parliamentary Labour Party.
"An investigation is now under way, and that will take place, and a result will come from that."
The Labour leader said the Harvey Weinstein controversy had highlighted the need for people to be able to report alleged abuse.
Mr Corbyn said: "But, behind all this is, actually, the atmosphere surrounding Harvey Weinstein and what he's done.
"And the atmosphere of abuse of women is a very, very serious one.
"There has to be a proper system of people being able to report - women particularly - being able to report if they have been abused in any way. And have it dealt with in a timely and proper manner."
Harvey Weinstein has "unequivocally denied" any allegations of non-consensual sex.
Mr Corbyn said he agreed with Prime Minister Theresa May that anyone with concerns about sexual harassment or abuse at Westminster should report them to the relevant authorities.
The Labour leader said: "The Prime Minister has also announced this morning that she supports, which I agree with her on, a process that the staff of any MP, of any party, can, and should report these matters to the House of Commons authority.
"Because, when there is an unequal power relationship in the workplace and women become vulnerable as a result of it, they have to be supported. They have to be protected.
"And, I say this to every employer that's listening: make sure that you have got processes in place that any of your staff that feel under threat, or are being abused by a more powerful colleague, then you have to have a process to deal with it."