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.
The judge ruled in March that parts of the court documents in the case should be remain private.
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.”
The hearing on permission is due to start at 10.30am.