King Charles provides a private allowance for Andrew Mountbatten-Windsor

Andrew Mountbatten-Windsor has been told that the allowance given to him by King Charles should not be used to fund his legal action against Thames Valley Police.

The King uses his own private money to support his brother and to accommodate him on his estate in Sandringham.

But a royal source said that this funding should not be used for a legal challenge being launched by Mountbatten-Windsor against the search warrants issued ahead of his arrest in February.

The former Prince Andrew was arrested on suspicion of misconduct in public office, in the wake of information that emerged from the Epstein files in the United States. Mountbatten-Windsor has consistently denied any wrongdoing linked to his association with Epstein.

Andrew Mountbatten-Windsor photographed leaving a police station in February

Mountbatten-Windsor is not a working royal - so Buckingham Palace no longer speaks on his behalf and is not involved in his legal battle.

But a royal source said the King's financial support for his brother should not be directed towards paying for the judicial review that Mountbatten-Windsor is seeking.

It's not been disclosed how much the King gives to Mountbatten-Windsor, but the funding for his brother was part of the arrangement when the former Prince Andrew was moved from his previous home at Royal Lodge in Windsor.

At the time of Mountbatten-Windsor's arrest, the King said the "law must take its course", and the Palace has made clear it is not part of the former Prince Andrew's legal pushback.

Mountbatten-Windsor's lawyers are understood to be challenging the lawfulness of search warrants used for Sandringham and at Royal Lodge relating to his arrest.

Thames Valley Police has confirmed it is "engaged in legal proceedings in relation to warrants previously obtained from the Central Criminal Court".

It added: "As these legal proceedings are currently ongoing, it would be inappropriate for us to comment further."

Mountbatten-Windsor, who lost his titles as a prince and Duke of York over his connections to the sex offender Jeffrey Epstein, wants a judicial review to consider the legality of the search warrants.

A court hearing will be held on Thursday afternoon as part of this bid to quash the warrants, with the hearing set to begin in private. The judge will initially hear a request by the police to keep some documents private.

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