Piers Morgan left American breakfast  TV in visible disbelief as he described the arrest of Andrew Mountbatten-Windsor as an “absolute bombshell” — before admitting one key detail in the saga “sounds preposterous.”

Appearing on Fox & Friends, Morgan was quizzed by hosts Lawrence Jones, Ainsley Earhardt and Brian Kilmeade about the dramatic scenes that unfolded at Sandringham on Andrew’s 66th birthday.

“It is an absolute bombshell,” Morgan said. “To put this in context, there has been no member of the Royal Family arrested in my lifetime. I’m 60 years old. You have to go back centuries to the last time that a member of the British Royal Family was arrested.”

He stressed the gravity of the moment, adding: “This is the King’s brother who remains eighth in line to the throne so this is, like I say, an absolute bombshell.”

The turning point came when Jones sought clarification on what baffled many American viewers. “Piers, just to be clear for those of us who don’t understand — even though his Royal titles were taken away, even though he was kicked out of the Palace and all the state, he’s not receiving a salary from the government any more, he still remains in the line of succession?”

Morgan did not shy away from the awkward truth. “Yeah I know it sounds preposterous but that is the current state of play,” he replied. “Now I think it’s very fanciful that he would ever accede to the throne under any circumstances and I think increasingly that is going to be ruled out anyway by the sequence of events.”

The former Good Morning Britain presenter went further, issuing a stark warning about the monarchy’s future. “I have never seen a bigger threat to the future of the monarchy than what is unfurling right now.”

Andrew was arrested by Thames Valley Police on suspicion of misconduct in public office after officers arrived at Wood Farm on the Sandringham Estate at 8am. Unmarked vehicles were seen leaving less than an hour later, with police now empowered to search properties linked to him and conduct formal interviews before a charging decision is made by prosecutors.

Despite losing his titles and public duties, Andrew remains eighth in line to the throne — behind Prince William, his three children, Prince Harry and Harry’s two children. The constitutional technicality proved almost as shocking to American viewers as the arrest itself.

Andrew has not commented on the latest developments and has consistently denied wrongdoing.