The British Board of Film Classification (BBFC) also said a higher rating may be required for bad language with sexual or misogynistic connotations.

However, the organisation said it would take a "less restrictive" approach to depictions of cannabis use in the future - while maintaining its current standards on other drugs.

It comes after research carried out by the BBFC found people were concerned by the "level of sexual detail, nudity and the duration of the sex scenes" in films rated 12A/12 by its previous 2019 guidelines.

The organisation - responsible for classifying cinema releases, hard-copy versions of films and TV programmes, as well as shows on Netflix in the UK - said it would now take a more "cautious" approach in the future.

"Similar content is now more likely to be rated 15," the BBFC said.

"However, the research also indicates that audiences are happy for classification to be more lenient towards some sex references at the 15/18 borderline, especially in comic contexts."

Public opinion shift

The BBFC says its new classification guidelines reflect shifts in public opinion about violence, drug use, sex and use of language.

It follows a public consultation involving 12,000 people across the UK.

Sexual violence remains the largest area of concern for UK audiences, as it was in 2019 when research was last conducted.

The research also found people are more concerned about depictions of violence on-screen in content across all age ratings, with audiences expressing unease over distressing or disturbing forms of violence depicted in some scenes.

"Going forward, a higher rating may be required for violence across all age-rating categories, especially when particularly intense or impactful scenes occur," the BBFC said.

The organisation should it would "continue to highlight suicide and self-harm in its content advice", as research showed audiences want to be warned of this type of content.

The research also showed audiences were more accepting of cannabis misuse "so long as it is not detailed, glamorised or frequent".

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'Society has changed'

BBFC president Natasha Kaplinsky said: "At the BBFC, we're dedicated to ensuring what we do is responsive to the ever-evolving world around us.

"Since we last asked people across the country what they thought about our standards, society has changed, and opinions have followed - it's fascinating how this vast body of new research reflects this.

"This is the first classification guidelines update I have overseen as president.

"Not only am I proud and thrilled to launch these findings, but as someone who has always looked to the BBFC for guidance for myself and my family, seeing first-hand the level of dedication and insight that went into this process has been eye-opening and inspiring."