Zayn Malik is writing a tell-all book.

A source told the Mail on Sunday: "This book is going to be explosive and Simon Cowell will be furious with Zayn and may even try to stop it coming out. But Zayn is determined to reveal the secrets behind the clean image that was always so fiercely protected by the band’s publicity machine."

Zayn is also expected to discuss his high-profile romances, including his broken engagement with Little Mix star Perrie Edwards and his current relationship with supermodel Gigi Hadid.

Zayn previously slammed One Direction's music, insisting it "wasn't me".

He said: "I wasn't 100 per cent behind the music. It wasn't me.

"It was music that was already given to us, and we were told this is what is going to sell to these people.

"As much as we were the biggest, most famous boy band in the world, it felt weird. We were told to be happy about something that we weren't happy about.

"Whenever I would suggest something, it was like it didn't fit us. There was just a general conception that the management already had of what they want for the band, and I just wasn't convinced with what we were selling."

Simon was furious with Zayn and said his comments were disrespectful to the group and those who worked with them.

He said: "It is a bit rude to the people who wrote all the hits with them. And to the other band members. I mean they all wrote a lot of the stuff.

"I think once he has had a chance to reflect on everything he will probably reconsider what he's said because it was a very, very democratic process in the band.

"Life could have been a lot worse, right?"