Sheikh Mohammed bin Rashid al-Maktoum has broken his silence on the Godolphin doping scandal and said that "the truth" would emerge from an ongoing inquiry.
The ruler of Dubai also said that his former trainer, Mahmood al-Zarooni, would never work with his horses again.
The British Horseracing Authority banned Zarooni for eight years after finding him guilty of administering anabolic steroids at his stables in Newmarket last year.
"I was shocked, really," Godolphin owner Sheikh Mohammed told the BBC.
"I have many trainers and if one of them does the wrong things, you know... They gave him eight years, and I gave him lifetime. Finished. He comes and sees some other friends but he will never come near horses."
Asked if he felt his reputation had been tarnished by the drugs stories, Sheikh Mohammed replied: "No. Of course if they think I know... I am clear and I still love horses and racing."
The BHA said in July the scandal, which caused serious embarrassment to Sheikh Mohammed, was a result of Zarooni acting alone without knowledge of his senior staff.
Zarooni, who won the Dubai World Cup – the world's richest horse race – for Godolphin in 2012 with Monterosso, as well as the St Leger and 1,000 Guineas, admitted administering prohibited substances to horses at the Moulton Paddocks stable.
Sheikh Mohammed closed the stable and ordered internal investigations. Assistant trainer Charlie Appleby was later put in charge of some 200 horses that had been in Zarooni's care.In September, Princess Haya, who is also a president of the International Equestrian Federation (FEI), appointed former London police chief Lord Stevens to oversee an internal inquiry into the sheikh's global equine interests.
Asked how horses could have been doped without his knowledge when he is famed for his attention to detail, Sheikh Mohammed said: "He [Zarooni] doped them not for racing, but for treatment long term. Now Lord Stevens will find out the whole story and we will all know what happened. He hasn't finished yet but I hope good luck for him. The truth will come out because of independent Lord Stevens."
In May, Sheikh Mohammed said the import, sale and purchase of anabolic steroids and giving them to horses would become criminal offences in the UAE.