The Metropolitan Police has referred itself to the Independent Office for Police Conduct (IOPC) over a letter containing allegations about the Duchess of Sussex's father, Thomas Markle Snr.
It comes as police in the Philippines investigate suspected child sex abuse images reportedly found at Mr Markle's former home.
The Met Police previously said it had shared the letter with Meghan in 2019 but did not tell other law enforcement about the accusations.
The force has now said a voluntary referral has been made to the IOPC "in respect of the decision not to inform other law enforcement agencies, and the decision to pass the letter to the office of the Duke and Duchess of Sussex".
The Met has also now said it intends to "make a number of referrals to relevant overseas law enforcement agencies in relation to the allegations contained within the letter".
"That process is under way and will be completed in the coming days."
In a statement to Sky News on Friday, Meghan said she was "deeply distressed" by the allegations about her father and added that a letter had been sent to the Met which was subsequently shared with her.
Mr Markle Snr has denied possessing the images, calling the accusations "sick lies", in an interview with the Daily Mail.
Meghan's half-brother, Thomas Markle Jr, on Friday told The Sun he discovered a stash of child sex abuse images belonging to their father at his former property in the Philippines and reported it to local police and the FBI.
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Mr Markle Snr moved to the Philippines in 2025 after suffering a series of strokes.
In December last year, the duchess contacted her father via a letter after he had his left leg amputated and told a newspaper he did not want to die while distanced from his daughter.
He is now learning to walk again at a nursing facility in Florida.
Harry and Meghan moved back to the UK in August, six years after they stepped down as working royals and relocated to the US.
(c) Sky News 2026: Met refers itself to police watchdog over handling of letter about Meghan's father
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