The International Equestrian Federation (FEI) has banned endurance rider Sheikh Mohammed bin Rashid al-Maktoum from the competition for six months.

The ruler of Dubai and the spouse of the president of the FEI, Princess Haya of Jordan, were also fined 4,500 Swiss Francs after his horse tested positive for banned substances.

Princess Haya recused herself from the case, given her relationship with the Sheikh. She has been a staunch anti-doping advocate. 

Reuters reports that in a statement, the Dubai ruler said he had no knowledge of any illegal substances being used.