The haul is nearly double the size of the last record haul of 300kg, made last year.

BBC: Australia makes largest meth seizure

In 1994 the Chinese delegation left with more than double the Japanese haul of 59 golds.

CNN: Japan evens the odds

That haul included a Champion Hurdle-Gold Cup double for trainer Kim Bailey on Alderbrook and Master Oats, Williamson becoming the 10th jockey to accomplish the feat and the first for 34 years.

BBC: Norman Williamson