Mel B has been blocked from discussing her relationship with Eddie Murphy.

The former Spice Girls singer had promised to ''set the record straight'' with her new autobiography 'Brutally Honest', but it looks like she's going to have to miss out a huge section of her life as the 57-year-old actor, with whom she has 11-year-old daughter Angel, has banned her from mentioning him or their sex life.

A source told The Sun newspaper: ''Mel has to be very careful about her chapter on Eddie, because they have a legal deal in place.

''That came in the aftermath of him denying being the dad of Angel and then working out a financial deal through lawyers.

''The publishers' legal team are looking at how to get around problematic aspects of it, but Mel will not be able to talk about the financials or personal aspects of Eddie's sex life. A book exposing the highs and lows of their relationship would not be helpful.''

The gagging clause was put in place in 2007 when Mel agreed to a cash settlement from the actor after a DNA proved that he was the biological father of Angel.

However, although her chapter on Eddie will be relatively short because of the legalities, Mel has vowed to reveal all on her marriage with Stephen Belafonte.

The 43-year-old singer split from the film producer - with whom she has Madison, six - last year after claiming that he had been physically and emotionally abusive to her.

She said: ''This book will show that abuse can happen to anyone.

''It is important my three girls, who I raise as a single mother, know how to break the chain of abuse -- along with any other woman who reads this book.''

Mel also has 19-year-old daughter Phoenix with Jimmy Gulzar.

'Brutally Honest' is expected to be released in November.