Socialite James Stunt has told a court he “didn’t know it was an offence” to ask his personal assistant to “forge” his signature so he could buy an Andy Warhol painting.

The 40-year-old said he was “jacked up on morphine” in a Los Angeles hospital when he sent an email to Francesca Sota telling her to “please forge my signature” so he could draw £320,000 from one of his bank accounts.

The former son-in-law of F1 tycoon Bernie Ecclestone is one of eight defendants on trial over an alleged multimillion-pound money-laundering operation.

Prosecutors at Leeds Cloth Hall Court have previously claimed that during the investigation into the alleged network “it became apparent that Stunt instructed Sota to forge his signature on an important financial document” in February 2015.

On Thursday, Stunt told the court that on that day he was “jacked up on morphine” because he was in hospital due to a tennis injury sustained at the Los Angeles home he was sharing with his then-wife Petra Ecclestone.

He said: “It was the first time I have ever tried morphine. I was floating on a cloud, you vomit and things, but it’s a wonderful feeling.”

Stunt said he had tried to buy a painting by the US artist with one of his “multiple bank accounts” but “made a human error and didn’t realise there weren’t enough funds in the account”.

Jurors have previously heard that on February 9 2015, Stunt told the Arbuthnot Latham private bank that he was going to write a cheque to be drawn on his account for £320,000.

Prosecutor Nicholas Clarke KC said a document was sent for Stunt to sign before they would allow him to draw the additional funds from the account.

The court heard an email from Stunt to Sota said: “Sorry to call so late was in hospital I made payment my bank is saying I need to sign something meaning they have not made them please forge my signature first thing in the morning get Lee or witness it yourself please this must be signed and emailed to the relevant parties. Thank you x.”

Later, it was said, Stunt wrote: “Call me as soon as you can I need that bank thing signed witnessed and sent to them or the payment won’t be sent that screws me badly!”

An email from Sota was later sent to the bank saying: “Please find attached the signed document by Mr Stunt and myself as a witness.”

Stunt told jurors he was “a man of integrity” and “didn’t prejudice a bank”.

He said: “It’s my own money, I think this (forgery) is a laughable charge.”

The defendant said he “didn’t mean to put (Sota) in any precarious position” and “didn’t know this was even an offence”.

“I didn’t mean forgery. Forge can mean a friendship, I could forge a friendship with you Your Honour,” Stunt said. “I meant, please make my signature in my name.

“I thought it was part of her duties (as a personal assistant).”

Stunt told the court that businessmen including his father and Bernie Ecclestone have stamps with their signatures on.

“I thought Miss Sota had full authority with my permission to stamp my signature.

“Bernie Ecclestone does it, my father does it, if that’s a crime you should lock up half the court.”

The court was shown a picture of Stunt with the-then Prince of Wales, Charles, which the defendant said was taken either at Clarence House or St James’ Palace.

He told the court “there are more than one photo of me and His Majesty”.

Stunt also said he knew former prime minister David Cameron “intimately”.

The jury has heard the alleged money-laundering operation saw £266 million deposited in the bank account of Bradford gold dealer Fowler Oldfield from 2014 to 2016.

Prosecutors say “criminal cash” was brought from all over the country to Fowler Oldfield’s premises in Hall Lane, Bradford, before the scheme “went national” and Stunt’s offices in London also started receiving money.

Heidi Buckler, 45, Greg Frankel, 44, Paul Miller, 45, Haroon Rashid, 51, Daniel Rawson, 45, Francesca Sota, 34, Stunt, 40 and Alexander Tulloch, 41, all deny money laundering. Stunt and Sota also deny forgery.

The trial continues.

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