Prince Harry was left floundering after the Antiguan premier publicly suggested he could be about to marry his new girlfriend Meghan Markle and offered him a honeymoon on the island.
Prime Minister Gaston Browne crashed through standard royal etiquette with his public speculation.
Harry appeared to grimace after the leader said rumours suggested that there "might be a princess soon" at a reception night on the Caribbean island.
Mr Browne said: "I understand that there may be a new addition to the royal family very soon.
"I am told that there may be a princess and I just want to say that should you make the decision to honeymoon - then Antigua and Barbuda want to welcome you."
The premier added: "We have been voted consistently as the best honeymoon destination in the Caribbean - and one of the best in the world - so there will be nowhere in the world as special to spend your honeymoon, when that day arrives."
Harry reportedly appeared to flush and looked down as Mr Browne made his comments.
The leader then compounded his gaffe by adding: "Whatever is done here, stays here. So do not worry," at a reception where he was set to meet six beauty queens.
Harry has only been dating Miss Markle, a US television actress, for a few months.
He has been fiercely protective of the couple's privacy and issued an unprecedented statement to the media a few weeks ago calling for restraint after what he described as a "wave of abuse and harassment" towards his girlfriend.
The Antiguan premier later said that he approved of Harry's choice, adding: "I believe Meghan is a very beautiful looking girl, they make a very good looking couple."
Despite the prince indicating that he is firmly off the market, at least one of the beauty queens at the event said she hoped they could change his mind.
Miss Antigua and Barbuda Leanda Ann Norville, who met the prince at the reception, said: "He was a gentleman. Of course I want to be his princess. Everyone at this party does. His girlfriend seems a nice lady, but I would be a good girlfriend for him."