The 22-year-old, partnered with horse Stardust, posted the fastest round-one time of 69.78sec at the ExCel London and followed it up with the quickest in the jump-off, 35.91, to seal victory.

This was 0.80 up on The Netherlands' Harrie Smolders, riding Monaco, who clocked 36.77 in the jump-off.

Bronze went to a second Briton, John Whitaker on Unick du Francportm in a time of 37.50.

Norway's Geir Gulliksen on VDL Groep Quatro and Britain's Ben Maher - the Olympic champion - on Faltic HB finished fourth and fifth, respectively.

Charles expressed his delight at the win, crediting the words of encouragement that his father, London 2012 Olympic team gold medallist Peter Charles, had given him.

"This is a bucket-list thing, I've grown up watching this show every year and it’s been one of my dreams to win the World Cup in London," Charles said.

"I chose to not watch anyone and he said okay, I trust you so good luck, you can do it - they were his last words before I went in and won it."

One of his main challengers for the win was Switzerland's Martin Fuchs, who appeared in contention for a medal with Conner Jei before knocking over a barrier, pushing him down to seventh.

Ireland's Denis Lynch is still top of the FEI Jumping World Cup Western European League standings with 39 points, but Charles' win puts him just one point behind.

Eduardo Pereira de Menezes of Brazil is a further five back.

The next of the Western European League event is scheduled to take place in Basel from January 12 to 16.