The 38-year-old World Equestrian Games gold medallist, riding Vanir Kamira, topped the standings with 26.8.

Townend, who had led for the majority of the competition, fell 0.3 shy in second place.

The Briton and mount Ballaghmor Class, in pole position after the dressage and cross-country events, were denied victory after they finished four seconds over the optimum time.

Australia's Christopher Burton, on board Graf Liberty, was third on 28.1.

While Townend was left disappointed, French could not contain her emotion after her triumph at the five-star event. 

"I’m very much not used to this – I can’t believe it,” said French.

“I woke up this morning thinking we could do it, then after I walked the course I thought that was it as that style of course really doesn’t suit her with several related distances.

"I could build the same course at home, in the same size arena as here and jump it 50 times and we wouldn’t jump clear. 

"In the nicest possible way, she’s a pain 362 days of the year, but I love her to bits and she comes into form at these big ones.”