"Despite clear denials, a false story ran in a UK newspaper today speculating about the relationship between The Duke of Sussex and The Duke of Cambridge," the statement read.
"For brothers who care so deeply about the issues surrounding mental health, the use of inflammatory language in this way is offensive and potentially harmful."
It followed a story in the Times of London on Monday, reporting that the Duke and Duchess of Sussex, Meghan and Harry, felt "pushed away" by William's "bullying attitude."
It came ahead of crisis talks being held by the Queen at Sandringham - the Queen's country estate in rural Norfolk, UK.
The Queen, Prince Charles, Prince William and Prince Harry will all attend the meeting. Meghan will phone in from Canada where she is currently residing with Archie.
Prince Philip was pictured leaving the estate this morning as he said to be too angry to speak to the pair. The Daily Mail claimed that when the news broke of Megxit last week, he shouted: "What the hell are they playing at?"
Meanwhile, according to the UK's Daily Express, the Queen was "alright", despite Meghan and Harry making their announcement on January 6 without her consent or her knowledge.