Parts of some documents in the Duke of Sussex’s claim against the Home Office over his police protection in the UK will remain secret, a High Court judge has ruled.

Harry is bringing legal action over a decision not to allow him to pay for police protection for himself and his family while in the UK.

The duke wants to bring his children to visit from the US, but he and his family are “unable to return to his home” because it is too dangerous, a representative previously said.

At a preliminary hearing last month, the High Court in London heard an application by both sides for some parts of the court documents in the case to be kept private.

The court was told that both the duke and the Home Office were agreed on the “vast majority” of what should be redacted from witness evidence and the document outlining the duke’s case.

In a judgment on Thursday, Mr Justice Swift said the bid to redact documents was allowed.

“This judgment does not consider the merits of that claim, it concerns only the extent to which it is necessary for information relied on in support of the claim to remain confidential.”

“Some of the information relied on concerns security arrangements put in place either for the claimant or for other public figures in the United Kingdom. For obvious reasons information on such matters usually remains confidential.”

Mr Justice Swift said that some parts of his reasons for the decision would have to remain confidential as well.

He added that editing out information from court documents would “avoid the risk that putting information into the public domain concerning security arrangements made on past occasions, and the general approach to whether and if so what arrangements should be made, may impair the effectiveness of arrangements in place now, or which may be put in place in the future”.

“Information about these matters would self-evidently be of interest to anyone wishing to harm a person within the scope of the security arrangements and would assist them to piece together previous practice with a view to anticipating present or future security provision,” he continued.

Thursday’s ruling only covers the redaction of documents and does not decide the duke’s claim against the Home Office or whether it can go ahead.

Harry is challenging the February 2020 decision of the Executive Committee for the Protection of Royalty and Public Figures (Ravec) over his security, after being told he would no longer be given the “same degree” of personal protective security when visiting.

The duke’s barrister, Shaheed Fatima QC, previously told the court that Harry considers the UK “is and always will be his home”.

A representative for Harry previously said the duke wants to fund the security himself, rather than ask taxpayers to foot the bill.

However, Robert Palmer QC, for the Home Office, previously told the court the duke’s offer of private funding was “irrelevant”.

In written submissions, he said: “Personal protective security by the police is not available on a privately financed basis, and Ravec does not make decisions on the provision of such security on the basis that any financial contribution could be sought or obtained to pay for it.”