Prince Harry switched on to his flirty best when he leaned over to whisper to his new sister-in-law Pippa Middleton about how beautiful she looked at the royal wedding.
“You do look very beautiful today – seriously,” he told her.
The dazzled best man, 26, voiced the nation's thoughts as he led Kate's radiant chief bridesmaid back up the aisle after their siblings' vows, reports the Sun.
Later the pair seemed to make a perfect couple themselves, as they stood side-by-side on the balcony of Buckingham Palace gazing down on the ecstatic crowds.
It also got many tongues wagging with suggestions that the pair looked such a good match that they might be the next royal romance.
Incidentally, Harry's on and off flame Chelsy Davy was also there.
Former England cricket captain Michael Vaughan jokingly took to Twitter to urge: "Make a move this afternoon, Harry."
Comedienne Katy Brand wrote: "Harry and Pippa whispering dirty, flirty little asides to each other."
Unluckily for Harry, she is seeing former England cricketer Alex Loudon.