A fuming Prince William is still reeling over his brother, Prince Harry , scoring a rare meeting with their father, King Charles III , and now he's given his dad an "ultimatum," RadarOnline.com can reveal.

William, 43, told his father, "It's me or Harry," according to a palace insider, as the future monarch has devoted his life to royal service. At the same time, his estranged younger sibling, 40, continues to stab his family in the back even after his "peace talks" with his dad. Article continues below advertisement

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"William's not about 'I told you so' or revenge – he's completely focused on what's best for the family," the source said of the prince's motives with his father.

Charles, 76, agree

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