King Charles has issued a firm ultimatum to Prince Andrew, warning that he may face the official removal of his royal titles unless he cooperates.

The 76-year-old monarch has conveyed his readiness to take decisive action if Prince Andrew, 65, does not voluntarily relinquish his dukedom and other honors, following revelations that Andrew misrepresented his connection with the convicted sex offender Jeffrey Epstein.

Insiders reveal to the Daily Mail that despite mounting evidence against him, the former Duke of York has shown a “remarkable lack of remorse” and remains defiant.

This stance, sources say, has been deemed “unacceptable” by the King.

Legally, King Charles would need parliamentary approval to strip Andrew of his titles, a lengthy process he would prefer to avoid to save parliamentary time and resources.

However, it has come to light that last week, Charles privately informed Andrew of the various options available to him if he does not step down voluntarily.

Some have questioned whether the act of making Queen Elizabeth’s second son simply set aside his titles is adequate in the circumstances.

But sources say that to involve Parliament when it is dealing with huge domestic and economic challenges, not to mention major global security issues, could have been seen as a waste of resources and taken months – or even a year – to conclude.

Forcing Andrew’s hand would bring about the same result far more swiftly.

King Charles was pictured arriving at Crathie Kirk church, near his Balmoral estate in Scotland, for a service on Sunday

Prince Andrew, Prince William and Prince Charles arrive to attend a Christmas Service at the Sandringham Estate in 2011

And with a narrowing window of opportunity to grasp before the situation spun further out of its control, the Palace made its move on Friday. 

The fact courtiers were even willing to consider taking the matter out of his hands – whether through Parliament or by other means – is believed to have ‘shocked’ Andrew into finally taking action.

A royal source said yesterday: ‘The thought of him still continuing to use the titles and honours that had been conferred upon him for another day, month or year while other options were explored and enactioned was intolerable, for the sake of the wider family. And at last, for the wider good, Andrew saw sense.’

Yesterday, in another world-beating exclusive, The Mail on Sunday revealed that Andrew tried to involve the Metropolitan Police and one of Queen Elizabeth’s most senior aides in a campaign to smear Virginia Giuffre, who had accused him of assaulting her as a teenager. 

A bombshell email obtained exposed how Andrew asked his taxpayer-funded police bodyguard to investigate the ‘lying’ young woman.

Shockingly, the prince passed on details of her date of birth and social security number, presumably given to him by Epstein.

He also claimed Virginia, who took her own life earlier this year, had criminal convictions, which has been strongly denied by her family.

An earlier email exposé proved that Andrew lied to Buckingham Palace and the British public when he claimed he had cut off all contact with his close friend in December 2010, following Epstein’s release from prison on child-sex charges.

Andrew pictured with Jeffrey Epstein in New York’s Central Park in 2011. Andrew refused to explain how he obtained Ms Giuffre’s nine-digit US social security number

Twelve weeks later he emailed the paedophile financier to say they were ‘in this together’ and sickeningly expressed his wish to ‘play some more soon’.

The revelations, ahead of the publication tomorrow of Ms Giuffre’s memoir, were considered a ‘tipping point’ for the Palace, prompting the King to move so decisively.

‘When the end came, it was relative quick, swift and ruthless,’ a source said. ‘Andrew may not have been able to read the room, but the Palace could.’

Another source added that while the announcement was an ‘imperfect outcome’, it was considered the best option in the circumstances. 

Several sources say that right until the end Andrew, who remains a prince by birthright, appeared to be in denial about the seriousness of his predicament and ‘clearly strongly believes in his own innocence’.

Where the latest developments leave him with his nearest and dearest is yet to play out.

He will not join the Royal Family for Christmas, but it is difficult to say whether he will ever be seen in public with them again, particularly when it comes to family funerals or services marking key religious events such as Easter.

Given that the King is Supreme Governor of the Church of England which maintains a Christian ethos towards the forgiveness of sinners, it would be challenging for Charles to ban his brother from church.

However, it is hoped that if the situation arises, Andrew will find ‘less prominent’ ways to attend than his recent scene-stealing appearance at the Duchess of Kent’s requiem mass, when the full awkwardness of family relations was on show. 

Suggestions that Prince William may take an even stronger line in the future, including banning his uncle from his Coronation, were described as ‘conjecture’ yesterday.

‘He’s in lockstep with his father on the actions taken,’ a source close to the future king said.

There has been concern among the wider family for Andrew’s personal health and wellbeing in recent years. 

Reports have suggested he is a ‘shell’ of the man he used to be, and the concerns may partly account for why the prince was allowed to issue his own wording and statement on Friday.

It also understood that the Palace intends to address the inclusion of Andrew’s biography on its official website as a member of the Royal Family in the coming days. It is not clear whether it will be further downgraded in light of recent developments – or simply deleted.