Prince Harry is seeking a judicial review against the refusal of the Home Office to allow him to personally pay for police protection when in the UK.
The US-based Duke of Sussex says his private security team does not have adequate jurisdiction abroad.
Prince Harry lost his tax-payer funded police security when he stepped back from royal duties in 2020.
He says he and his family are “unable to return to his home” as it is too dangerous for them.
A government spokesperson said the UK’s “protective security system is rigorous and proportionate”.
They added: “It is our long-standing policy not to provide detailed information on those arrangements. To do so could compromise their integrity and affect individuals’ security.”
Prince Harry’s application for a judicial review – a challenge in the High Court against the decision of a public body or government department – follows a security incident in London in July 2021 when his car was chased by photographers as he left a charity event.
A legal representative for Prince Harry said the claim was filed in September “to challenge the decision-making behind the security procedures, in the hopes that this could be re-evaluated for the obvious and necessary protection required”.
Prince Harry wants to personally fund police protection, “not to impose on the taxpayer”, they added.