A mum allowed her two daughters to be subjected to more than a decade of rape and perverted abuse at the hands of their stepfather, a jury heard.

The 40-year-old woman sometimes joined in – forcing one daughter to take part in a naked sex act with her and her husband on the sofa at their Tandridge home, it was alleged at a trial.

The older girl was repeatedly forced to endure depraved sexual ordeals until the night before she left home to live with her boyfriend, the court heard on Tuesday.

Then it was the turn of the younger girl, who was repeatedly raped and abused, Jonathan Davies, prosecuting, told Guildford Crown Court.

The male defendant, 39, denied 10 counts of rape, one of indecent assault, two of sexual activity with a child, one of engaging in sex in the presence of a child, and one of inciting a child to take part in sexual activities.

The female defendant denied two offences of cruelty, one of indecent assault and one of engaging in sex in the presence of a child.

The jury heard the alleged offences took place over a period of 11 years between March 1996 and April 2007.

Mr Davies said the older daughter came home one day to find the couple having sex and was told by the male defendant to "come on, join in".

Mr Davies said: "Eventually the woman defendant said 'enough'. The male defendant swore at the girl and told her to go to bed.

"The male defendant said 'did you enjoy that? Don't tell anyone'," he added.

Mr Davies continued, saying the man insisted on having sex with the older girl one last time, in a wooded area, just before she began a relationship with a boyfriend.

He said the stepfather told the girl "one more time won't hurt".

The prosecutor said the male defendant then turned his attention to the younger girl, raping and abusing her repeatedly.

He said both girls suffered a prolonged catalogue of abuse from their stepdad and were "wilfully neglected and abandoned by their mother".

The prosecutor said: "She did nothing to protect them. She was not only aware of the abuse, she observed it, and, on occasions, took part in it."

The defendants, who cannot be named for legal reasons, were finally arrested and charged after the younger girl confided in someone at school about her experiences, the court was told.

The trial continues.