The UK police watchdog is to investigate the Metropolitan Police’s handing of a letter containing allegations against Thomas Markle that was handed to his daughter, the Duchess of Sussex, in 2019.

The Independent Office for Police Conduct (IOPC) said it had decided an investigation was required into the force’s “failure to pass on allegations of serious offending… to relevant overseas authorities at the time”.

The letter, written by Markle’s first wife Roslyn Loveless, is believed to have contained claims about Meghan’s father.

He has strongly denied recent allegations that he had possessed images of child abuse, describing them as “sick lies”.

On Thursday the Met said it had voluntarily referred itself to the IOPC.

The letter at the heart of the IOPC investigation was sent to the Met’s royal protection team by Loveless, who divorced Thomas Markle in 1975 and died in 2024.

The handwritten letter was then passed to Meghan in January 2019, with the duchess saying last week that it had “made troubling and disturbing allegations against my father”.

Meghan did not provide any details but said it had given her sufficient reason to not visit Thomas Markle and not allow him to meet his grandchildren, Archie and Lilibet.

Scotland Yard said the letter contained claims about offending outside the UK and that it had been forwarded to “the office of the Duke and Duchess of Sussex for their awareness”.

The IOPC will consider why the Met did not share the contents of the letter with other law enforcement agencies, in the UK or overseas.

The Met said on Thursday that it intended to make further referrals to “relevant overseas law enforcement agencies”, a process which it expected to be completed “in the coming days”.

The letter was forwarded by officers to the Sussexes’ royal office rather than to Meghan personally, while there have been reports that the Met did not keep a copy of the letter and had to ask for one from the Sussexes.

The watchdog will have to consider how the contents of the letter were treated by the force at the time.

Noel Rasmussen, Thomas Markle’s granddaughter and niece of the Duchess of Sussex, previously told the BBC she was “deeply troubled by the questions surrounding the Metropolitan Police’s handling of the information it received”.

“If allegations of this seriousness were brought to the attention of authorities, it is reasonable to ask what steps were taken [and] why the information was not shared with other law enforcement agencies.”

Reports of the Met’s handline of the letter emerged as Thomas Markle’s son had told the police in the Philippines about material which was alleged to contain sexual images of children, which he had claimed to have found in possessions belonging to Meghan’s father.

Thomas Markle had been in the Philippines in December 2025, undergoing hospital treatment, when Meghan wrote to him to end all contact.

Authorities in the Philippines have begun investigating the claims. Police there have obtained a warrant to examine devices seized from Markle’s former home.

Four boxes of material, including computers, phones, hard drives and old videotapes were handed to police by Meghan’s half-brother, Thomas Markle Jr, last week.

However, officers in Cebu needed a court warrant before they can examine the items.

Thomas Markle Sr has strongly denied all the allegations against him. He has been backed by his daughter Samantha, who has dismissed the claims against her father as “fake”.

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