EXCLUSIVE: Queen Camilla Preparing for Combat — Prince Harry's Peace Talks Have Monarch Planning to Show Him and Meghan Markle Who's Boss

Rampaging Queen Camilla is laying down the law for the Duke and Duchess of Sussex ahead of their anticipated return to the royal fold – and now courtiers anticipate a colossal catfight between the consort of Britain's King Charles and Prince Harry's headstrong wife, Meghan [Markle], RadarOnline.com can reveal.

An insider confided: "Meghan is willing to be conciliatory and take the high road with a lot of people – but Camilla is a different story. She's convinced Camilla has been trying to undermine her and paint her as the villain from day one, and she's adamant that she won't open herself up to more cruelty."

"She's not planning to start a scene, but she's not going to pretend everything is fine and play nice with Camilla. She's told Harry she refuses to be a punching bag anymore – especially for someone she believes has spent years trying to destroy her reputation," the insider added.

According to palace insiders, Camilla is running rampant through the palace after her cancer-stricken husband's assurances that her standing will remain solid – even if he passes away and Prince William, 43, ascends to the throne while she's still alive.

But Camilla, 78, is said to be seething that sentimental Charles, 77, is even considering mending fences with redheaded renegade Harry, who, with Markle, left behind life as working royals in the U.K. in 2020 to chase fame and fortune in the former Suits star's home state of California.

Sources said the couple's defection from the palace didn't bother Camilla as much as Harry's scathing tell-all, Spare, which painted the current queen as a backbiting bully who planted stories in the press to tear down the Sussexes and shine her own star.

Sources added scheming Camilla has worked hard to win back the public in the U.K. and was furious that Harry wrote that he and brother William begged their father not to marry her following the 1997 car crash death of their beloved mother, Princess Diana.

As RadarOnline.com readers know, Charles and Camilla notoriously carried on a longtime affair during his doomed marriage to Diana, and was villainized by the press after their divorce in 1996.

Furthermore, sources said protective Camilla is also steaming that her spouse, who Harry, 41, has criticized as an emotionally distant dad – and who considers Markle, 44, a manipulative puppet master – is even allowing them to return for a reconciliation.

As far as the queen is concerned, sources explain, biracial Markle has betrayed the crown by suggesting some of her husband's kin were racist for raising concerns about the skin color of the couple's then-unborn son, Archie, and by claiming the royals turned a blind eye toward her mental health struggles while living in the U.K.

Courtiers say Camilla has begrudgingly accepted that Charles wants to reconcile with his youngest son – and spend time with his Sussex grandkids, Prince Archie, 6, and Princess Lilibet, 4 – but she's demanding that Harry and Markle defer to her as queen, respect her rank and know their place – or face the consequences.

However, the insider cautioned: "If Camilla wants to keep playing dirty, Markle is ready to hit back. Harry has told her all the family secrets, so she has plenty of ammunition."