It is understood that at one point the Princess was so smitten with Dr Khan that she contemplated converting to Islam so they could marry.
THE TELEGRAPH: His hair is greyer and his features are more rounded but Dr Hasnat Khan's affection for Diana, Princess of Wales, remains undiminished by the passing of more than a decade.
The heart surgeon the late Princess described as "Mr Wonderful" is sitting on a sea-green sofa at his home in Pakistan.
Dressed in a white shirt, faded jeans and trainers, he fondly recalls the woman he shared an intimate relationship with until just months before her death.
To Dr Khan, Diana was first and foremost a warm, generous woman who just happened to be a princess.
"I found her a very normal person with great qualities," he says, choosing his words with immense care.
"I think she did great work all over the world not just for the UK but for everyone. That is very important."
After meeting at the Royal Brompton Hospital, where the Princess was visiting a friend who was recovering from heart surgery, they pursued a discreet, two-year affair that finished in the early summer of 1997. Dr Hasnat Khan: Princess Diana and me >>> By Massoud Ansari in Jehlum and Andrew Alderson
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