Mohamed Al-Fayed blamed himself for the death of his son, Dodi, and Princess Diana, according to a report by journalist Andrew Neil.
Mr Al-Fayed, the billionaire former owner of Harrods department store and Fulham FC, died last week at the age of 94.
Former Sunday Times editor Mr Neil on Tuesday penned an article for MailOnline, recounting his personal dealings with the eccentric Egyptian-born mogul.
He recalled visiting Mr Al-Fayed to pay his respects in 1997, shortly after his film producer son, Dodi, and Diana, Princess of Wales, who were in a relationship, died in a car crash in Paris.
He had been hired by Mr Al-Fayed as a media consultant after he left The Sunday Times, as the businessman was reportedly keen to build a media empire.
Dodi and the Princess of Wales, who were in a relationship, were killed in August 1997 as they tried to evade paparazzi as they left Mr Al-Fayed’s Ritz hotel.
Mr Neil wrote: “He recounted how Dodi had come up with the cockamamie plan to shake off the paparazzi by escaping via the back entrance of The Ritz hotel, where he and Diana were ensconced in the Imperial Suite.
“But his security detail said they did not work for Dodi and that to leave the hotel in the manner he wanted would require Mohamed’s approval.
“So Dodi called his dad. His dad spoke to security. He then told Dodi he should just relax with Diana at the Ritz. They were safe and secure in one of the world’s greatest hotel suites. Why leave? Get room service and watch a film.
“But Dodi told him Diana was distraught because a paparazzi mob had gathered outside.”
Mr Al-Fayed owned the Ritz hotel, but Dodi reportedly wanted to take Diana to the “privacy and anonymity” of his flat just off Paris’ famous Champs-Elysées so Diana could “leave with nothing but happy memories”.
“Mohammed caved in to his son,” wrote Mr Neil for MailOnline.
“He looked at me with a tear in his eye as he recounted this story and said: ‘I will never forgive myself for going along with Dodi’s plan. He would still be alive but for me.’”
Mr Al-Fayed “passed away peacefully of old age” last Wednesday, August 30, his family confirmed in a statement released on Friday.
A funeral for him was helf after Friday prayers at London Central Mosque in Regent’s Park, Sky News reported.