LONDON, England (CNN) -- The sole survivor of the crash that killed Princess Diana has told a court he still cannot remember the incident but does not support the conspiracy theories surrounding it.
Bodyguard Trevor Rees, formerly known as Trevor Rees-Jones, was the front-seat passenger in the Mercedes that carried Diana, her boyfriend, Dodi Fayed, and their driver, Henri Paul.
He sustained serious injuries in the August 31, 1997 crash and testified that he received anonymous phone calls and letters after the accident, threatening him to keep quiet.
He said the caller told him to keep quiet, saying, "We know who you are, we know where you are, and we know where you live."
Rees said he didn't take the calls or letters seriously.
A lawyer also asked Rees about a supposed encounter with a woman in which he told her, "If I remember, they're going to kill me." Rees said he didn't recall the conversation and found it unlikely he ever made the remark.
Rees, who still has a visible scar from the accident over his left eye, told the court he remembers nothing new about the crash, which, he has said, was an accident.
He has said the last thing he remembers that night was leaving the Ritz Hotel in Paris, and that his next memory is more than a week later, in his hospital bed, when his parents told him everyone else in the car was dead.
Rees suffered major injuries to his lower jaw, the base of his brain, and his pulmonary system and has had several surgeries and hospitalizations, some of which al Fayed paid for.
Rees also testified that he did not support the allegations by Dodi Fayed's father, Mohamed al Fayed, that British security services were behind the crash. He denied the security services paid him to change his story.
At the time of the crash, Rees was working for al Fayed's security team and was assigned to guard Dodi Fayed. He was also protecting the princess because she was Fayed's companion on the trip.
He no longer works on al Fayed's security team. Rees has said what was once a good relationship with his former employer has broken down, largely because he does into support al Fayed's conspiracy theories about the crash.
"I am not a part of any conspiracy to suppress the truth at all," Rees testified. "All I have ever done is given the truth as I see it."
In 2000, Rees published a book, "The Bodyguard's Story: Diana, the Crash, and the Sole Survivor," offering his account of the events surrounding the crash. He said al Fayed tried unsuccessfully to stop the book's publication in England.
Rees told CNN he wrote the book to give a definitive account of what he remembered and knew, but also to counter al Fayed's accusations that his unprofessionalism caused the accident. Rees also said proceeds from the book helped pay his legal bills.
During the morning session, Rees testified that he had two flashbacks in the months after the crash, but his psychiatrist told him they were false memories.
In the first, Rees said, he recalled hearing the voice of a woman -- apparently Diana -- calling out, "Dodi" from the back seat of the car. In the second flashback, Rees said he recalled seeing a paparazzi motorbike next to the car.
Lawyer Ian Burnett then read from a letter written by Al Fayed to Lord Stevens, who investigated the crash for the British police. In the letter, Al Fayed says Rees is lying about losing his memory.
"He knows the detail which the security services are so eager to suppress," Al Fayed wrote, alluding to his belief that the crash was part of a murder plot.
Rees testified that he was not lying about his memory loss: "I have no memory of -- after leaving the back of the hotel, that's my last true memory."
Rees also said claims the couple visited a jeweler's in Monte Carlo to buy an engagement ring in late August 1997 were untrue.
British authorities hold an inquest whenever someone dies in suspicious circumstances. A judge, who is also called a coroner, holds hearings to determine how the person died, but he will not determine blame or apportion guilt.
Although Diana and Dodi Fayed died in Paris, a British coroner must still investigate because their bodies were returned to Britain. The inquest does not involve driver Henri Paul because his body remained in France.
British authorities had to wait to begin the inquest until after French authorities concluded their investigation, which lasted from August 1997 to late 2003. The inquest then began but immediately adjourned so that British police could do their own report, which was needed for the British inquest.
The British police inquiry took almost three years and concluded in December 2006. The inquest then resumed in October 2007 and is expected to last four to six months. E-mail to a friend
CNN's Teresa Martini contributed to this report.