EXCLUSIVE INVESTIGATION: Royals at War! How Carnage is Breaking Out Inside Palace Over Harry, Meghan and Shamed Andrew Windsor

All hell has broken loose at the palace, RadarOnline.com can reveal.

Royals are at war as carnage is breaking out inside the palace, fueled by bitter divisions involving Prince Harry, Meghan Markle, and shamed Andrew Windsor that are threatening to tear the monarchy apart.

Princess Kate vs. Duchess Meghan

Duchess Meghan is planning her UK reinvasion – she and Prince Harry are expected to visit this summer – and she's already planning her looks, sources said. She's determined to outshine Kate [Middleton] and will spend whatever it takes to make it happen, an insider said.

"Meghan is meticulous when it comes to picking out her wardrobe at the best of times, but now that she's gearing up for this trip, it has become all-consuming. She's going to need all the protection she can get when she goes back to the UK, and she really does view being well-dressed as her suit of armor."

Middleton isn't quaking in her designer boots. "She doesn't view Meghan as a threat. She's more of a nuisance. Kate knows that in the end, Meghan will do herself in. She always does."

Prince Harry vs. Prince William

King Charles is ready to roll out the red carpet for Harry and Meghan when they come to Britain together in July – but it's causing havoc with a number of senior royals, especially Prince William, who's clashing with his father and getting so bent out of shape it's threatening to erupt into a full-scale civil war, sources said.

"William sees Harry as a real threat to the monarchy, and the future king is taking steps to protect himself and the crown," said an insider.

"William is also flat-out refusing to be in the same room as Harry when he does come back. If he has to leave town to avoid him, he will. There's no chance of any sort of peace between him and his brother now or ever."

Queen Camilla vs. Duchess Meghan

Camilla is trying to sabotage Markle and Harry's return to the royal fold – and now courtiers anticipate a colossal catfight between the ladies.

"Meghan is willing to be conciliatory and take the high road with a lot of people – but Camilla is a different story," said a palace insider.

"Meghan is convinced Camilla has been trying to undermine her and paint her as the villain from day one. She's not planning to start a scene, but she's not going to pretend everything is fine and play nice."

Princess Beatrice vs. Princess Eugenie

Sisters at war! Princess Eugenie has disowned her disgraced father, Andrew – but older sister Princess Beatrice is unwilling to do the same, causing major tension between the stressed-out siblings, sources said.

"This was – and still is – a nightmare decision for Eugenie. She wrestled with it for an enormous amount of time, and even now, there's a huge sense of sadness and loss at being estranged from her own flesh and blood," an insider shared.

Princess Kate vs. Queen Camilla

Cue the eye roll... Camilla is once again boozing hard, sources say, and throwing her weight around at the palace – much to Princess Kate's amusement.

"Camilla can try all she wants, but she's not THE queen, never will be," said a source. "When Kate becomes queen, she will most definitely be regarded as the queen, and that drives Camilla nuts." It also fuels their long-standing rivalry.

"Camilla tries to humiliate Kate at every turn, but it never works. Kate is too strong of a woman."