A hoax call that led Prince Harry into sharing his thoughts on politics, family and the plight of some imaginary penguins exposes "huge flaws" in security in his new life outside palace walls, it is feared.
Harry spoke at length to Russian hoaxers he thought were Greta Thunberg and her father and made comments distancing himself from most of the royal family and criticising the US president. It has raised serious security concerns as the Sussexes begin a life away from the aides and protection the prince has known all his life.
Harry shared his thoughts on the "good soul" of Boris Johnson, the "right but not easy" choice to leave the working royal family, and appeared to criticise environmental campaigning styles led by his own brother.
He sympathised with the plight of the invented island of Chunga-Changa, said he would never work with the "sad meat" at McDonald's and laughed at the idea of a marriage between Greta Thunberg and Prince George.
He even volunteered to put "Greta" in contact with someone who could help free 50 penguins purportedly "stuck at customs in Belarus" and take them to the North Pole - penguins are creatures of the southern hemisphere.
Harry is currently living in a waterside Canadian mansion with Meghan Markle and 10-month-old Archie, from where he spoke to Russian YouTubers Vladimir Kuznestsov and Alexey Stolyarov on the landline on New Year's Eve and again on January 22.
Harry has previously expressed admiration for the Swedish girl's campaigning. His father, Charles, met the real Greta Thunberg at Davos this year.
As well as making awkward listening for Harry, the calls raise serious concerns about security now he is leaving the protection of Buckingham Palace and experienced aides.
After news broke of the prank, royal observers expressed sympathy but also deep concern at the Sussexes' vulnerability as celebrities now based largely in North America.
The hoax calls also gave an extraordinary insight into Harry's relationship with his family, as he spoke about the decision to leave, saying: "The right decision isn't always the easy one."
The comments are likely to cause hurt and disquiet at the palace, and follow weeks of detailed discussions about the Sussexes' settlement as they leave to pursue financial independence.
The call also saw Harry lament the royal family's approach to the media, which he claimed was trying to "destroy our [the Sussexes'] reputation" and "sink us".
He said: "For most, all of my life, I've always been part of a family and part of a country that's scared of the tabloid media because they have so much power and influence and no morals."
He also expressed the view that the world was being led by "some very sick people".