Funeral of Britain's Prince Philip in Windsor
Britain's Queen Elizabeth II watches as pallbearers carry the coffin of the Britain's Prince Philip during his funeral at St George's Chapel, Windsor Castle, in Windsor, Britain, April 17, 2021. Dominic Lipinski/Pool via REUTERS

It was wrong to hold a secret hearing which decided that the will of Prince Philip, Queen Elizabeth's late husband, should be sealed and kept private for 90 years, lawyers for a newspaper told the Court of Appeal in London on Wednesday.

Philip, the Duke of Edinburgh, died in April last year aged 99 at Windsor Castle after more than seven decades of marriage to the queen.

In September, Andrew McFarlane, the president of the High Court's Family Division, disclosed that he had agreed Philip's will should be sealed up "and that no copy of the will should be made for the record or kept on the court file".

He said that by a convention dating back to 1910, the death of a senior royal is followed by an application to seal the will, with such hearings and judgments kept private.

McFarlane said he was the custodian of a safe containing more than 30 envelopes with the wills of dead royals.

The Guardian newspaper is appealing against a decision to exclude the press and public from a hearing on July 28 last year. An earlier hearing that agreed to this exclusion was also held in secret.

The first the media became aware of the hearings was when McFarlane's ruling was made public two months later.

"An entirely private hearing such as this is the most serious interference with open justice," Caoilfhionn Gallagher, the Guardian's lawyer, told the court, describing the decision as "disproportionate and unjustified".

The paper is arguing that McFarlane was wrong not to allow the media a chance to question whether the application to seal the will should proceed in private.

Gallagher said the paper "does not and could not" at this stage challenge McFarlane's substantive ruling to seal the will, but was likely to seek to make submissions as a third party should the application be re-heard.

The appeal is being heard by three of Britain's most senior judges - Master of the Rolls Geoffrey Vos; Victoria Sharp, the president of the Queen's Bench Division; and Justice Eleanor King.

In Britain, once probate - the administering of a deceased's estate - is complete, wills are normally made public.

McFarlane had ruled that publishing Philip's will would be "contrary to the aim of maintaining the dignity of the Sovereign". He also agreed to exclude the value of the estate from the grant of probate.