Scott won the Longines Global Champions Tour Grand Prix of London for the second straight year to thrill the home fans.
Hello Mr President triumphed in a seven-horse jump-off, winning in a time of 38.88 seconds.
It was record-breaking Scott’s 11 LGCT title and his second of the year following his success on Ursula in Mexico.
Scott said: “I’m absolutely delighted. It was a bit unexpected to be honest, because he is a young horse, he’s a fantastic horse, but I didn’t expect that he was ready to be able to win this Grand Prix.
“It’s amazing to win here in London in front of this amazing crowd, they really give us British riders an unbelievable reception when we come in and out.”
Scott believes Ursula and Hello Mr President complement each other perfectly and added: “Ursula is an unbelievable horse, but it is just great to have the next generation coming through to help her out. The future is bright for us.”