According to the Guardian, which successfully applied for reporting restrictions to be lifted alongside Bloomberg and the Press Association, she claimed in a High Court hearing on Thursday that the former Ritz and Daily Telegraph owner has not paid any of a £100m divorce order made almost a year ago.
She also claimed that the 87-year-old had halved a monthly allowance of £60,000 owed to her without consultation.
Sir Frederick was required to pay his ex-wife £50m in August last year and another £50m in May this year. He could face a prison sentence or a hefty fine if found guilty of contempt of court for failing to pay.
Mr Justice Jonathan Cohen adjourned the case to obtain further evidence as to Sir Frederick’s mental capacity to conduct proceedings.
The proceedings yesterday were held largely in person with only Sir Frederick attending via video link.

Pictured: The Barclay brothers bought Brecqhou for £2.3m nearly 30 years ago.
Sir Frederick’s lawyer, Charles Howard QC, reportedly told the Court that Sir Frederick’s daughter, Amanda, was no longer paying her father’s legal costs, which were now being funded by his nephews by way of a loan.
In May last year, Justice Cohen was highly critical of Sir Frederick when he sold his yacht for an estimated £125m but failed to use the proceeds to pay his wife, calling it “reprehensible”.
He also said: “[Sir Frederick] is a public figure who should have been aware of the potential consequences of disobedience of court orders and his behaviour in the proceedings should not be allowed to pass completely under the radar.”
Sir Frederick is well known in the Channel Islands after he and his late brother – Sir David Barclay – bought Brecqhou in 1993 and built a castle on it. Sir David died in January 2021.
Sir Frederick has faced various legal issues over the past two years. These have included claims that Sir David’s sons bugged one of Sir Frederick’s conversations about selling the Ritz Hotel. That dispute was settled last year and the Ritz was sold.
The twins were estimated to be worth £7bn prior to Sir David’s death.
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