Andrew with his former wife Sarah, Duchess of York, who has also been the subject of unwanted headlines recently

CHRIS JACKSON/GETTY IMAGES

A royal source said: “It feels like we are reaching a tipping point.”

The Times has also learnt that Andrew invited Cai Qi, the senior Chinese official at the centre of the Beijing spy case, into Buckingham Palace for lunch in 2018.

Another option open to the King to reprimand his brother would be to banish him from the Order of the Garter.

While the removal of Andrew’s dukedom is likely to receive public support, with a YouGov poll this summer showing 67 per cent of people favoured of stripping him of the title, the palace is said to be aware that it would take up valuable parliamentary time.

Given that there are procedural difficulties with such a sanction, it is hoped that Andrew may now act with “honour”, a source said, and voluntarily give up his titles.

It is the strongest line the palace has taken with Andrew since the late Queen stripped him of his royal role in 2019.

Another obvious and visible act of self sacrifice for the greater good of the monarchy is said to be for him to voluntarily move out of Royal Lodge.

Royal Lodge

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However, he has a private long-term lease on the property with the Crown Estate and has hitherto shown no desire to move out of the 30-room home in Windsor where he lives with his former wife, Sarah Ferguson.

Now the scandal is overshadowing the work of the monarchy, which this week included a message from the King to support UK farmers and a meeting with indigenous elders at Australia House.

Yet Andrew continues to dominate the headlines.

He stepped back from royal duties nearly six years ago after his disastrous interview with Newsnight in which he claimed not to remember meeting Virginia Giuffre, a victim of the convicted sex offender Epstein.

He told the journalist Emily Maitlis that he had ceased all contact with Epstein after visiting him in New York at the end of 2010.

The meeting, he said, was an opportunity to do the “honourable” thing and break off his friendship with him in person.

However, an email published on Sunday revealed that Andrew had been in touch with Epstein later than he claimed.

In February 2011, after a picture was published showing Andrew with his arm around Giuffre’s waist, the duke wrote to Epstein saying: “It would seem we are in this together and will have to rise above it. Otherwise keep in close touch and we’ll play some more soon!!!!”

The Duke of York with Virginia Giuffre and Ghislaine Maxwell

VIRGINIA ROBERTS GIUFFRE

For the palace, this was a significant moment in the long-running scandal as it demonstrated a lie, presented a serious reputational risk to the monarchy and came at a critical point in Charles’s reign.

While those close to Charles give Andrew credit for not publicly criticising his family, unlike the Duke of Sussex, they believe that he should now preserve his late mother’s legacy by giving up his titles and removing the risk of further reputational damage to the institution.

If not, it is understood that the King would be resolute in taking the difficult steps required to sanction his brother.

The scandal surrounding Andrew continues to grow. An extract was published this week from the posthumous memoir of Virginia Giuffre, which is released next week.

In it, Giuffre, who died by suicide in April aged 41, described Andrew as “entitled” and claimed that Andrew “believed that having sex with me was his birthright”.

The duke has always denied claims that he had sex with Giuffre and settled a civil case against her for £12 million with no admission of liability.

Fresh allegations emerged on Thursday in which it was revealed that Andrew had met at least three times with Cai Qi, the Chinese official at the centre of the Beijing spy case.

Cai is one of the most senior figures in China’s Communist Party and a close ally of Xi Jinping, China’s president.

Cai Qi, one of the most senior members of the Chinese Communist Party, met the duke on several occasions

HAN YAN/XINHUA/ALAMY LIVE NEWS

Andrew met with Cai at least three times between 2018 and 2019, including, the Times has learnt, as Andrew’s lunch guest at Buckingham Palace.

A meeting on May 15, 2018, which was listed in the Court Circular, the official record of royal duties, Cai “was received by” Andrew at the palace “and remained to luncheon”.

On another occasion, Andrew was Cai’s guest of honour at a dinner at China’s Foreign Affairs office in Beijing on April 10, 2018.

At the request of the British government, the Princess Royal also met Cai on an official visit to China in 2017.

It is not the first time that Andrew has become embroiled in issues which relate to suspicions of Chinese spy activity.

Last year, he was forced to rescind his invitation to a royal family Christmas lunch when it emerged that Yang Tengbo, a businessman who had been appointed founder of Andrew’s Pitch@Palace enterprise in China, was banned from the UK by the Home Office and accused by MI5 of being a Chinese spy. Yang denies the claim.

A royal source said: “We’re taking the fundamental issues extremely seriously.

“It’s very much not the case that the palace is turning a blind eye to it all. We are taking every fresh allegation extremely seriously and reviewing the potential opportunities while being aware that those steps that can be taken have largely been enacted.”

They added: “It is a source of immense frustration and concern for the King that there continue to be holes picked in the duke’s story.”

Meanwhile, emails sent to an address previously used by the duke with the “royal.uk” domain address were this week returned as “undelivered” for the first time since his departure from public office.

The Duke has been approached for comment.