The King was left in “disbelief” after an alpaca dressed in a crown and waistcoat with a golden bow tie sneezed on him as he went to say hello.
Nine-year-old Hephner spectacularly fluffed his lines when he was introduced to the King outside the Australian War Memorial in Canberra.
When the King stroked his nose the animal left off a loud sneeze - provoking laughter.
Thousands turned out to greet the King and Queen - with fans waving flags and banners.
The throng included Robert Fletcher brought his alpaca - named Hephner as his mother was called Playgirl - on its lead to meet the King.
The nine-year-old had a new gold crown and suit and gold bow tie for the event.
Robert, of Goulburn, New South Wales, uses his alpaca as a support animal for charities and nursing homes.
He said while waiting for Charles: “My wife found the crown and thought it was fitting. I think he loves his crown very much.
“He has lots of outfits but it’s a special day so he is in a suit and bow tie as well.
“Hephner has met a few famous people before but this is the King. He wants to meet the King.
“He doesn’t bite and he doesn’t spit. He’s always on his best behaviour anyway.
“And he is a pro-monarchy alpaca.”
When Charles came close Robert shook his hand and introduced the King to the animal.
But as the King gently petted him within seconds the alpaca let out a loud sneeze
Robert said afterwards: “I got to shake his hand and then Hephner sneezed.
“The King just looked in disbelief.
“But it’s just who Hephner is. He is an alpaca after all”.
The royal couple received huge cheers as they walked 200 metres from the Australian War Memorial Council Member and Australian Army Veteran, ‘Aunty’ Lorraine Hatton.
Thousands lined the walkway.
John Mordes, 21, bunked off work to see the King and Queen.
He said: “He asked me if I was off university and I said I should be in work instead.
“I will go back to work and tell my manager I was on my break.
“I came down because he is the King and Queen and I don’t know when I will ever see them again.
“He looks really good and had a firm handshake.”
Wendy Davies, 67 of Melbourne, met Queen Camilla who was wearing
She said: “I said welcome to Australia and shook her hand. She is looking beautiful.”
At the end of the walk the couple stood at the For Our Country Memorial where Sub Lieutenant Jordan Bradshaw, an Indigenous serving member of the Australian Defence Force who will also sound the didgeridoo.
