A parliamentary inquiry has been launched into online pornography in the face of "intolerable" levels of sexual violence against women and girls in Britain.

The inquiry by the All-Parliamentary Group on Commercial Sexual Exploitation is a response to growing concern about the harmful effects of online pornography. 

It follows revelations that Wayne Couzens, the former police officer who was handed a whole-life sentence for the kidnap, rape and murder of Sarah Everard, was attracted to "brutal, sexual pornography".

In April last year, a police chief warned that growing numbers of British men between the ages of 18 and 26 are looking at child abuse images online after becoming "desensitised" to legal pornography.

Earlier this year, it was reported that online porn websites are promoting "sexually violent" videos.

In June, Child Commissioner Rachel de Souza warned: "Viewing hardcore pornography from a young age can warp boys' views of what they can expect from girls, and normalise behaviour from girls to do things they don't want to do."

The inquiry will be carried out by a cross-party group of MPs led by Dame Diana Johnson MP.

It will run for six months and hear evidence from a range of international experts on how the pornography industry operates, harms associated with porn, and existing laws aimed at addressing these harms.

Johnson said: "It's time for MPs to confront the role of pornography in fuelling violence against women. The intolerable level of sexual violence that is perpetrated day in day out in this country is not inevitable. There is nothing 'natural' about it.

"So the question is, what in our culture is fuelling men's violence against women – and what do we do about it? No answer to that critical question is complete without addressing the role of online pornography.

"We know that mainstream pornography is replete with violence and degradation, that the majority of users are men, and that currently children are able to access porn companies' websites. International pornography companies generate huge profits, but what price are we all paying for this?

"This landmark cross-party inquiry will investigate what part the pornography industry is playing in fuelling men's violence against women – and what Parliament should do about it."

Christian charity CARE, which has been campaigning for age verification, said the inquiry was "long overdue". 

Spokesperson for the charity, James Mildred, said, "The links between extreme pornography and sexual violence are becoming clearer and clearer.

"Pornography has been implicated in a host of tragic cases involving the rape and murder of women in recent years. It is described as a contributing factor by those working with victims of sexual violence across the UK. And it has been named as a motivator of sexual harassment in schools.

"Politicians are right to seek evidence from a wide range of stakeholders on this and we call on them to consider a wide range of actions." 

Recent polling commissioned by CARE has revealed widespread concern about harms of pornography, with six in 10 adults saying they were "concerned that pornography is inspiring sexual violence against women and girls."

Seven in 10 adults also agreed that the government "should stop websites publishing extreme pornography that portrays violence or non-consensual sex."

In a separate poll, eight in 10 people expressed support for mandatory age checks on porn sites, with an age limit set at 18 years.

Mr Mildred added, "As Dame Diana Johnson, Chair of the APPG, says, 'The intolerable level of sexual violence that is perpetrated day in day out in this country is not inevitable'. Evaluating and addressing the harms of pornography is one way to challenge this toxic culture."