Nigella Lawson has told a court that she had taken cocaine in the past, but said the idea that she is a ‘drug addict or habitual user of cocaine is absolutely ridiculous’.

The TV cook said she took cocaine with her late husband John Diamond when he found out he had terminal cancer, and in July 2010 when she was being ‘subjected to intimate terrorism by Mr Saatchi’.

Speaking in court – where she is giving evidence in the trial of her former personal assistants on fraud charges – she said: “I have never been a drug addict. I’ve never been a habitual user. There are two times in my life when I have used cocaine.”

Nigella, 53, went on to say the first was when her late husband Mr Diamond found out his cancer was terminal, and she had it with him on six occasions. “It gave him some escape,” she said.

She said she had responsibility for looking after him and the family and earning a living. The star said she spoke to a doctor at the time.

Speaking about the second time in her life, she said it was when a friend gave the drug to her. “There was another time I took cocaine. In July 2010 I was having a very very difficult time. I felt subjected to intimate terrorism by Mr Saatchi,” she said.

She added that she felt ‘isolated and in fear of… just unhappy’.

“A friend of mine offered me some cocaine. I took it,” she said.

Nigella said it ‘completely spooked’ her.

She said: “The idea that I am a drug addict or habitual user of cocaine is absolutely ridiculous.”

The chef said this was her evidence under oath.

Nigella faced dozens of photographers and television crews from around the world as she arrived at Isleworth Crown Court in west London.

Her former PAs, Francesca Grillo and her sister Elisabetta, sometimes referred to as Lisa, are accused of committing fraud by abusing their positions by using a company credit card for personal gain.

Prosecutors claim the Italian sisters lived the ”high life”, spending the money on designer clothes and handbags. The pair are accused of using credit cards loaned to them by the TV cook and her ex-husband Mr Saatchi to spend more than £685,000 on themselves, the jury has heard.

Nigella said Mr Saatchi ‘told everyone’ he was taking cocaine out of her nose after he was photographed holding her neck at Scotts restaurant.

She claimed the incident was actually sparked when she commented on a person walking by with a baby. “I said ‘I’m so looking forward to having grandchildren’,” she told the court. “He grabbed me by the throat and said ‘I’m the only person you should be concerned with’.”

Nigella admitted taking cannabis in the last year of her marriage to Mr Saatchi.

“I have to be honest, I have smoked the odd joint,” she said. “I found it made an intolerable situation tolerable. It’s a false friend and not a good idea. I found the answer was in changing the situation and trying to create a tolerable situation for me and my family. I have to say, since freeing myself from a brilliant but brutal man, I’m now totally cannabis, cocaine, any drug-free.”

Elisabetta, 41, and co-defendant Francesca, 35, both of Kensington Gardens Square, Bayswater, west London, deny the charge against them.