The two famously struck up a bond more than 20 years ago, when the Spice Girls performed at the royal gala, with Geri later going on to serenade the future king with a rendition of Happy Birthday To You at a public celebration.
Two decades on, it seems the pair still have a special relationship, as she cheekily dubbed him a “Spice Boy” as they came together for a Prince’s Trust fundraiser.
Speaking at the event, Geri praised Charles as a modern and forward-thinking royal, saying: “He’s part of our heritage. We consider him as a Spice Boy.
“I feel like Prince Charles his royal highness is part of the landscape of the Spice Girls, our journey. He was there from the beginning.
“To see him just grow and shine, our future king, I just think it’s brilliant what he does and I really admire him as a representation of our country.”
She added: “I feel like we should be really proud of what he does. He’s a modern man, he’s a modern royal in everything he does. He has consciousness. He thinks about the world that we live in.”
Geri, who was at the event with fellow Spice Girl Emma Bunton, was then asked if there was any chance Prince Charles would attend their forthcoming reunion tour, to which she said: “He’s always welcome, always welcome.”
However, Victoria Beckham will not be joining them, instead choosing to focus on her fashion business.