Britney Spears has accused Justin Timberlake of cheating on her with two famous women – including a huge 1990s pop star.

The ‘Toxic’ singer, 41, makes the claims in her upcoming bombshell memoir ‘The Woman in Me’, out 24 October, in which she also reveals she aborted her ‘SexyBack’ singer ex’s baby as he wasn’t ready to be a dad when they were together.

Fans in Mexico who got the book a week early after it went on sale by mistake before its publishing date say it says Britney claims Justin secretly bedded two celebs – one of whom is believed to be All Saints singer Nicole Appleton.

Britney and Justin – who is now married to and has two sons with 41-year-old actress Jessica Biel – dated from 1999 to 2002 after they met as kids on Disney’s ‘The Mickey Mouse Club’.

In 2000 it was widely rumoured Justin and Nicole, now 48, had an affair after they were photographed slipping into the St Martins Lane Hotel, west London, where he was staying after a night out.

According to The Sun, one fan with an early copy of Britney’s book said on X: “Britney mentions that she knew JT was unfaithful, first with the All Saints girl and then with a celebrity who is still very famous, married and has kids now… and that in revenge she had a one-time lay down with (dancer) Wade Robson.”

The Sun also reported Britney uses her book to reveal she lost her virginity at around the age of 13 or 14, well before finding fame – and years ahead of her making headlines over the status of her virginity when she was dating Justin.

Her fling with ex Colin Farrell, now 47, apparently is barely a footnote in the book, The Sun said, with Britney branding their short romance “impulsive” in her memoir.

Mum-of-two Britney, whose husband Sam Asghari, 29, filed from divorce from her in August, says in her upcoming memoir about her abortion while dating Justin: “I loved Justin so much. I always expected us to have a family together one day. This would just be much earlier than I’d anticipated.

“But Justin definitely wasn’t happy about the pregnancy. He said we weren’t ready to have a baby in our lives, that we were way too young.”