British television chef Nigella Lawson was so "off her head" on drugs that her assistants were able to go on spending sprees with her credit card, her ex-husband Charles Saatchi said in court documents revealed Tuesday. The comments by art collector Saatchi emerged ahead of the trial of Italian sisters Francesca and Elisabetta Grillo, who are accused of committing fraud while working as personal assistants to the celebrity couple. In an email read out to a London court, Saatchi told his ex-wife: "Of course now the Grillos will get off on the basis that you... were so off your heads on drugs that you allowed the sisters to spend whatever they liked." The 70-year-old multimillionaire added: "I believe every word they have said." The judge ruled that the email could be reported, despite the trial having not yet started. Saatchi and Lawson, who has made her own millions with TV shows in Britain and the United States as well as a string of cookbooks, split after 10 years of marriage earlier this year. They announced their divorce after shocking pictures appeared in the British newspapers of Saatchi grabbing Lawson by the neck outside a London restaurant. He accepted a police caution over the incident but said he was "disappointed" she had refused to say publicly that he had not abused her. Lawson, the daughter of former British finance minister Nigel Lawson, is expected to give evidence during the Grillo trial. Defence barristers acting for the Italian sisters had wanted details of Lawson's alleged drug use to be heard in court. The court heard that Saatchi had learned the defendants were set to accuse Lawson of taking drugs, and was "completely astounded by the scale of drug use set out in the statements". "Nevertheless I did believe the allegations that I'm referring to in the email," he said in a police statement read to the court. Lawson is set to be grilled on her alleged drug use, after the judge concluded: "I will allow questions of Miss Lawson and witnesses as to the alleged taking of prescribed drugs or proscribed drugs." Saatchi, a former advertising baron who now owns London's Saatchi Gallery of contemporary art, married Lawson in 2003. She has two children from her marriage to journalist John Diamond, who died of throat cancer in 2001. Saatchi has one daughter from his previous marriage.