Justin Timberlake is reportedly being "eaten up" over his ex-girlfriend Britney Spears' much-hyped memoir

Multiple sources told Page Six about his apparent fears over the release of Britney's memoir 'The Woman in Me' on 24 October: "He's very curious what she'll reveal from their relationship. It's eating at him."

A recent report by Us Weekly said Britney's book is set to go after Justin "hard".

But a publishing insider told Page Six the autobiography is "not a takedown" of anyone.

They added: "This is Britney finally getting a chance to tell her empowering story, and it's nothing more than that."

At the time of his break-up with the singer, Justin told Barbara Walters during an interview he had made a pact with Britney not to "say specifically why" they split.

When pressed about rumours Britney cheated on him, Justin didn't try and deny them.

He instead said: "Honestly, we're not perfect. I don't judge anybody."

Britney also refused to address the rumour when Diane Sawyer asked her in a TV chat what she had done wrong in her relationship with Justin.

The mum-of-two singer - who has been worrying fans by posting a series of knife-dancing videos on social media in the wake of her husband Sam Asghari, 29, filling from divorce from her in August - said: "I think everyone has a side of their story to make them feel a certain way... and I'm not technically saying he's wrong, but I'm not technically saying he's right either."

Justin was slammed by Britney fans when his chat with Barbara Walters resurfaced as part of the 'Framing Britney Spears' documentary.

He issued an apology to his former flame amid the criticism, saying: "I am deeply sorry for the times in my life where my actions contributed to the problem, where I spoke out of turn, or did not speak up for what was right.

Justin also said on Instagram he had "failed" the singer despite his "respect" for her.

He added: "I know this apology is a first step and doesn't absolve the past.

"I want to take accountability for my own missteps in all of this... I can do better and I will do better."