Met Police received letter about Meghan Markle's father in 2019

London's Metropolitan Police has confirmed the force received a letter about Meghan Markle's father in January 2019 but did not share it with other agencies.

In a statement received by the ABC, a spokesperson for the Met Police said the letter contained "a number of claims about alleged offending outside the United Kingdom".

It comes after Meghan, Duchess of Sussex, revealed on Friday that she was informed in 2018 about "disturbing allegations" against her father, Thomas Markle, which prompted her to keep her children away from him.

International media earlier reported claims that child sexual abuse material had been found at Mr Markle's former home in the Philippines.

In an interview with the Daily Mail, Mr Markle denied possessing the images, calling the accusations "sick lies".

The 2019 letter was referred to MPS Protection Command "to raise concerns in relation to the security of the Duchess of Sussex" and to the office of the Duke and Duchess of Sussex.

But it was not shared with other law enforcement agencies, the spokesperson said.

The spokesperson added that the force was reviewing its handling of the matter, including whether it should call in the police watchdog. 

Authorities in the Philippines are investigating the allegations, according to UK media.

In the US, an FBI spokesperson said it was "aware of the allegations and would provide support, as appropriate, to the Philippine authorities". 

Prince Harry, the second son of King Charles III and estranged brother of heir to the throne Prince William, married Meghan at Windsor Castle in May 2018.

The couple left Britain and quit royal duties in 2020.

But they made an unexpected return with their two children to live in the United Kingdom in August.

ABC/Wires