Shadukhi, an English language student whose father is said to have recently retired from the Ministry of the Interior, was convicted of false imprisonment, making threats to kill and causing actual bodily harm. He was found not guilty of rape and causing grievous bodily harm with intent, and cleared of unlawful wounding and a second actual bodily harm charge after the jury failed to reach verdicts.

Nicholas Atkinson QC, for the prosecution, said that two days before the trial officials at the Saudi Arabian embassy tried to bribe the victim into dropping the case. The Foreign Office said last night that it was investigating that allegation.

Judge van der Werff told Shadukhi: "You kept her under your control at all times and you subjected her to various sorts of torture ... tying her up with wire and Sellotape and keeping her like that for long periods. It was a terrible time for her, a period of her life she will never be able to forget." He said the teenager had terminated her pregnancy.

The court was told that the girl had arrived in Britain with Shadukhi in January last year and he locked her in his Rotherhithe flat. Mr Atkinson said: "The defendant would secure her hands and feet with tape and put her in the bath and push her under the water. On one occasion he stabbed her feet in the bath with a kitchen knife so she saw the water turning red with her blood." He said Shadukhi made her stand half-dressed for hours, hit her with a mop handle and whipped her with a mobile phone charger.

The teenager said that when he forced her head under the water, Shadukhi would say: "This is the last day of your life. You don't deserve to live. I have to get rid of you."

Shadukhi denied all the charges, claiming the victim was lying and her injuries were either self-inflicted or the result of her fall.