Mohamed Al Fayed's first reaction to the news of Princess Diana's death was to blame the Duke of Edinburgh, her inquest has heard.
Mohammed Al Fayed blamed Prince Philip for Diana's death
He rushed to Paris by jet on hearing of the car crash there which also killed his son, Dodi, on 31 August 1997.
Bodyguard Kieran Wingfield, who revealed Diana's death, said his boss had "exploded" and made "allegations".
"He said something like 'I hope the British Government and Prince Philip are happy now'," said Mr Wingfield.
When questioned, the bodyguard said he believed the reaction had been "just an explosion of grief".
In December, the inquest heard that, within seconds of hearing of the crash, Mr Al Fayed had declared it a "plot".
Mr Wingfield also referred to a television programme, centred on possible conspiracy theories, which he was asked to participate in.
The bodyguard said: "I had no doubt in my mind that it was a tragic accident so I refused to take part in the programme."
And, when asked by counsel to the inquest, Ian Burnett QC, how his employer had reacted, the bodyguard told the inquest: "He wasn't best pleased at all, he started ranting at me, he was saying ... he was incoherent a lot of the time, he was talking about Prince Philip, he was also talking about the British government, he was swearing a lot."
After being asked by Mr Al Fayed to prove his loyalty, Mr Wingfield said he had taken a period of leave.
He told the inquest: "I went on leave and considered my position and I thought, 'You know, I can't continue like this'."
Regarding this decision, Mr Wingfield told the jury: "I believe if I had stayed in the organisation, I would have been asked to do things which were going to support the conspiracy theory and so I resigned."
Mr Wingfield, a former Royal Marine, also described how the princess's boyfriend devised a decoy plan to evade the paparazzi on the night of the crash.
He claimed the idea was for both Mr Wingfield and his colleague Trevor Rees - formerly Rees Jones - to leave by the front of Paris' Ritz hotel while Henri Paul drove the couple from the back.
Following objections from both men, he was persuaded to allow Mr Rees to accompany the couple - but still from the back of the hotel.
Mr Wingfield said Dodi then insisted: "It's OK, it's been okayed by MF. It's been okayed by my father."
"I have total recall because when Dodi said that, I remember that feeling that I got ... once Mr [Al] Fayed was mentioned in any capacity like that, in that organisation, argument was pointless," he added.
Kieran Wingfield was Princess Diana's bodyguard
The bodyguard said he spoke to the couple to confirm they would meet at Dodi's flat. This, he said, was the last time he spoke to them.
Later, when he arrived at the apartment they were not there and Mr Rees was not responding to calls on his mobile.
When questioned about the physical state of Henri Paul, who was over the UK drink-drive limit when he drove the Mercedes carrying Diana and Dodi, the bodyguard told the inquest: "There has been a lot of speculation about this.
"People say 'You should have known', but there was nothing in Henri Paul's demeanour that he had been drinking and Henri Paul wasn't my focus of attention."
Earlier, he told the inquest of his frustrations relating to the security measures taken during a Mediterranean cruise on Mohamed Al Fayed's luxury yacht, the Jonikal, in the summer of 1997.
Mr Wingfield, known as Kes, said the extra manpower had been needed to assess the destinations the couple had wanted to visit and provide him and Mr Rees with time off.
"I believe eight was the minimum required for the task on the Jonikal. Not because [they were] staying on the boat, [but] in the evening the couple went ashore and that's when we would have really needed the eight," he said.
The bodyguard, who joined Mohamed Al Fayed's security team in 1992, said he had been told about the plan to provide the couple with only two bodyguards by his employer a few weeks before the cruise.
Mr Wingfield told the hearing: "When he informed me the trip was going to happen soon I asked who else was coming on the task, meaning which other protection officers were going to be with [me] and he informed me it was Trevor Rees Jones and that was it.
"I suggested to Mr [Al] Fayed that was not enough to provide adequate cover. His words to me were 'I want this to be low key. It's only going to be for two or three days'."