Charles Saatchi has admitted that he saw his ex-wife Nigella Lawson take drugs during the final years of their marriage, despite denying it in court.

The ad executive previously said in the recent fraud trial against her former assistants the Grillo Sisters that he had ‘never. never seen any evidence’ of the TV chef taking anything.

However he has now said in a statement that this was not the case.

“The truth is that she was taking illegal drugs secretly throughout the last years of our marriage, often with her own child (Cosima) when she was far too young to smoke or even drink,” Saatchi explained. “Drug taking took place at an alarmingly frequent rate.

“That this practice seems to be considered acceptable behaviour in sections of the Press is deeply disturbing, as is the ­notion that you can teach your children that drugs are a justifiable way to make an unbearable situation bearable.”

Nigella – currently a judge on new Channel 4 show The Taste – admitted at the trial that she had smoked cannabis in front of her children.

She also confessed to taking cocaine on a number of occasions, firstly to cope with the news of former husband John Diamond’s terminal cancer, and later as her marriage to Saatchi ran into problems.

Meanwhile Saatchi also revealed that Lawson began an affair with him before Diamond’s death in 2001, saying he “deeply regretted” his actions.

However representatives for the TV chef have told the Sunday People that Diamond gave his blessing to the partnership prior to his death.

“John himself sanctioned the ­relationship when he knew he was going to die.

“He was very keen on his young children having a ­father figure so actively encouraged Nigella to date Saatchi.”