EXCLUSIVE: Queen Camilla 'Demanding King Charles Choose Between Her and Prince Harry'

Queen Camilla flew into a drunken rage after learning hubby King Charles was welcoming son Prince Harry and his family back to Britain with open arms, according to sources who said Her Royal Highness attacked the cancer-stricken monarch with a booze-soaked ultimatum: It's him or me, RadarOnline.com can reveal.

"Harry and Meghan [Markle]'s return to the U.K. has caused total chaos within the Firm," a royal insider said.

Homesick Harry and wife Markle recently left California and hightailed back to his homeland for what's been characterized as an extended stay.

Insiders said the arrangement won't affect the Duke and Duchess of Sussex's chosen status as nonworking members of the royal family – with some sources believing former Suits star Markle has already been offered a lucrative acting gig in the U.K.

The Sussexes have reportedly chosen a non-royal residence outside of London, and their two kids, who've been raised in Montecito, Calif., are attending nearby schools – despite Harry's concerns over security in the U.K.

Sentimental Charles is said to be overjoyed about the prospect of more time with his second-born son, American daughter-in-law and youngest grandchildren – Prince Archie, 7, and Princess Lilibet, 5 – who've lived thousands of miles away with their parents in the U.S.

However, sources said Camilla – Charles' longtime mistress who eventually married the then-Prince of Wales in 2005 – is furious over her stepson and his spouse weaseling their way back into the monarch's good graces.

Palace sources said in the face of Camilla's unseemly tantrum, Charles is pledging to stand by the woman he married nearly eight years after the death of Princess Diana – his ex-wife and mother of Harry and heir to the throne Prince William – while secretly striving to mend his fractured family bonds.

Insiders said as Camilla seethes with rage, she has an unlikely ally in unforgiving stepson William, who is said to still be steamed over the Sussexes' bridge-burning interviews trashing the royal family and his sibling's scathing comments in Spare.

Sources suspect William remains irate over the Sussexes' loose lips darkening the final days of his and Harry's late grandparents, Queen Elizabeth and Prince Philip, and how his brother painted him as a petty hothead in Spare and claimed the future king's wife, Princess Kate, made Markle cry.

Royal expert Kinsey Schofield recently told Page Six that William's circle believes "money and inheritance are part of the calculation" leading to the Sussexes' homecoming as the sickly 77-year-old king's days are numbered.