RICHARD EDEN: As the royal expert who revealed Harry has quit Britain, I know what the Queen would have done - and what Charles must now do...

Queen Elizabeth was a wise woman. And when she needed to take decisive action, she did.

That is why she decided the Duke and Duchess of Sussex could not be allowed to combine royal duties with seeking their fortune overseas.

And why she ignored Prince Harry’s efforts to persuade her otherwise.

In his best-selling memoir, Spare, Harry tries to convince readers that his grandmother was bamboozled into taking a tough line against him and Meghan by scheming courtiers.

In my opinion, however, Her Late Majesty knew exactly what she was doing and why.

Now, King Charles needs to take a leaf out of his mother’s book – and be decisive when it comes to his younger son and his role as a Counsellor of State.

As things stand, California-based Prince Harry could still be called on to stand in for his father in some circumstances because he remains a Counsellor of State – which is surely now intolerable.

The situation has since become even more urgent because of the King’s cancer treatment

In today's Daily Mail, in my social diary Eden Confidential, I reveal that Harry has updated his records in this country to make it crystal clear that he no longer lives in Britain.

Filings published by Companies House for ‘Prince Henry Charles Albert David Duke of Sussex’ record that his ‘New Country/State Usually Resident’ is now the United States of America. It was previously recorded as the United Kingdom.

It represents a sharp about-turn for Harry, who declared soon after announcing his decision to quit royal duties in 2020: ‘The UK is my home and a place that I love. That will never change.’

What could have helped bring about that unforeseen change is the growing pressure on US President Joe Biden to release Harry’s visa records.

The conservative Heritage Foundation think tank has been pushing the Department of Homeland Security to open its dossier on Harry under America’s freedom of information laws.

After he admitted taking cocaine in his memoirs, the prince has faced questions over how he had been able to move to the USA, where admitting drug use can block a visa application.

Now, campaigners have seized on comments made by the American ambassador to London that he would not be deported while Biden, a Democrat, was president.

The Heritage Foundation, which has gone to court to seek the release of the files, has submitted the Ambassador’s remarks as part of its case.

With this in mind, Harry’s new filing at Companies House – for his eco travel venture Travalyst – is a ‘fact on the ground’, a declaration that he is in California to stay.

Yet this raises other questions for the prince, and serious ones.

If America really is his home, how can he remain as a Counsellor of State, one of seven members of the Royal Family who can deputise for the Monarch if he is abroad or unwell?

By law, Counsellors of State are required to have a UK domicile, but Harry has no home here after King Charles asked the Duke and Duchess of Sussex to vacate Frogmore Cottage, a gift from the late Queen.

Harry, pictured with wife Meghan, declared soon after announcing his decision to quit royal duties in 2020: ‘The UK is my home and a place that I love. That will never change'

Until 2022, the Counsellors of State were Queen Camilla, William, Harry, Prince Andrew and his elder daughter Princess Beatrice.

However, many considered this situation unsuitable as neither Harry, the Duke of York, nor Beatrice are working royals.

Later that year, the King asked parliament to add his sister, Princess Anne, and youngest brother, Prince Edward, to the list.

It was reported that the King decided not to remove Harry and Andrew because he did not want to escalate family tensions and believed it was unlikely either would ever be required to deputise for him.

It would be wrong, though, to imagine that the role is a mere honorific.

Courtiers were notably keen to ensure that William returned to Britain from last year’s solo trip to New York before the King and Queen departed for their state visit to France on the same day.

Continuity matters.

The situation has since become even more urgent because of the King’s cancer treatment.

Now, the King needs to take decisive action and remove Harry as a Counsellor of State.

How on earth can someone who has officially left Britain be allowed to stand in for our country’s head of state?

Even the prospect of such an intolerable situation is putting the Monarchy in danger.

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