The film has been an unparalleled box office smash.

But the reported tensions between Fifty Shades Of Grey's director Sam Taylor-Johnson and the books' writer E.L. James have meant the two follow-up films' may have to be made under a different filmmaker.

The Sun has reported that the British director is keen to leave the franchise due to her constant on-set feuds with the author, despite previously claiming that she had 'signed on' to work on the sequels.

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Out of the franchise? Sam Taylor-Johnson is reportedly keen to pull out of directing the Fifty Shades Of Grey sequels after on-going bust ups with the books' author, E.L. James

A senior film insider told newspaper's Dan Wootton: 'Sam won't be back for the Fifty Shades sequels. She wants out and Universal knows that's the right decision.

'Her relationship with Erika has become absolutely toxic – they despise each other and blame each other for the problems with the film.'

Sam and E.L. - who signed a £3 million deal with Universal and Focus Films giving them the rights to her trio of books, which also gave her creative control of the movies - are said to have clashed numerous times about sex scenes as the author wanted to make the movie racier.

The source also claimed that most of the rows between the two were due to the author's wishes for the film to be as explicit as the book.

Difficult working relationship: E.L. James and the director have admitted that they found working together a challenge due to different artistic ideals

'But Sam pushed back because she wanted the movie to be more than just a collection of S&M scenes,' they added.

It was not officially confirmed that Sam would return to direct the sequels, although she had hinted that she was in the pipeline.

'I have a feeling discussions are going on behind closed doors but I've heard nothing so I'm as in the dark as everybody else on this,' the director revealed in a recent interview with The Independent.

A representative for Sam has told MailOnline that 'the studio have not committed to a sequel as yet' and that they decline to comment further on the matter.

Sam has openly admitted she and E.L would 'often clash' while making the film and she recently revealed she was banned from using a jellyfish in a sex scene, while the author also admitted the pair 'butted heads'.

Tension: E.L James (left) and Sam Taylor-Johnson (right) have toured the world together to promote the film along with the film's leading stars, including Dakota Johnson (centre)

Despite E.L.'s bust-ups with Sam, the two main stars of the movie, Jamie Dornan and Dakota Johnson - who play Christian Grey and Anastasia Steele - were said to have been happy with the filmmaker.

And although they are fans of working with her, they won't have the option to leave the franchise as they have signed tight contracts to keep them in the next two films, each which will be based on the follow-up novels Fifty Shades Darker and Fifty Shades Freed.

In a previous interview, director Sam admitted that filming the controversial film with the writer close at hand was often trying.

'It was difficult, I'm not going to lie,' she confessed.

'We would have proper on-set barneys and I'm not confrontational. But it was about finding a way between the two of us.'

'It was difficult': The British filmmaker has previously admitted to the challenge of working with the author

Success: E.L. is said to have wanted to keep the film as close to the erotic book as possible

Hollywood sources previously claimed that the director and author even rowed about the final word in the film, with Sam favouring 'red', a 'safe word' used in the bedroom by the protagonists, and James insisting on 'stop'.

It was, says one insider, 'the most petty and ridiculous argument in the world' and the climax of months of tension between the pair.

But E.L - who has sold 100million copies of her novel - apparently, 'was given a lot of power and has used every opportunity to flex that power'.

Another source who spoke to the Mail last week week claims the popular writer even threatened to tell her millions of fans across the world to boycott cinemas when the film was released on Valentine's Day if she didn't get her own way.

Erotic: The film is filled with raunchy and intimate scenes between the lead characters Christian Grey (Jamie Dornan) and Anastacia Steele (Dakota Johnson)

Sam recently responded rather bluntly to these rumours: 'I should hope not,' she retorted, when asked about them.

Despite the on-going professional scuffle between the two women, Fifty Shades Of Grey has gone on to become a huge success.

The raunchy film dominated cinemas at the weekend with ticket sales of £13.5 million since its release on Friday.

It outstripped the competition - taking in more in ticket sales than the rest of the top 10 films combined and becoming the most successful 18-certificate film ever in the UK and Ireland.

MailOnline has contacted a representative Universal and is awaiting comment.