According to Prince Harry’s witness statement, the newspaper owners struck a “secret agreement” with officials at Buckingham Palace to put off legal claims from members of the Royal Family.

That alleged agreement, which has not been disclosed in court, had delayed Prince Harry from bringing his own case, his lawyers say.

Prince Harry says that he first became aware of the alleged deal in around 2012.

At that time, he learnt that royal staff were starting legal action for phone hacking – and he believed he and his brother had been personally targeted too.

When the brothers consulted officials or the Royal Family’s top solicitor, he says they were told that they could not begin their own legal action.

“The rationale behind this was that a secret agreement had been reached between the institution and senior executives at News Group Newspapers, whereby members of the Royal Family would bring phone hacking claims only at the conclusion of [all other cases] and at that stage the claims would be admitted or settled with an apology,” the statement said.

“The reason for this was to avoid the situation where a member of the Royal Family would have to sit in the witness box and recount the specific details of the private and highly-sensitive voicemails that had been intercepted.”

Prince Harry said courtiers were “incredibly nervous” about a repeat of the damaging disclosure of an intimate phone call between his father and Camilla, the Queen Consort, which had been intercepted and published at a time when King Charles was still married to Diana. In the infamous phone recording, the prince was heard telling Camilla he wanted to be with her, and making highly intimate comments.

“This agreement, including the promises from NGN for delayed resolution was, obviously, a major factor as to why no claim was brought by me at that time,” said Prince Harry.

NGN denies any deal existed.

This case is one of three major cases that the Duke of Sussex has made against tabloid newspapers, all alleging unlawful information gathering. The other cases concern the Daily Mirror and Daily Mail groups.

He alleges that evidence disclosed since the criminal trials – which related to phone hacking at the now-closed News of the World – prove he was serially targeted by its sister title, the Sun.

Prince Harry accuses its journalists and private investigators working for them of obtaining private and confidential information from when he was 11 or 12-years-old – including details on his personal life and movements.