Mohamed al-Fayed's unanswered Diana questions

LONDON, Aug 24 (Reuters) A decade after Princess Diana and Dodi al-Fayed died in a car crash in a Paris tunnel, Mohamed al-Fayed, Dodi's father, argues the deaths were not an accident.

Here are the main questions he believes have not been answered and the issues he says have been covered up.

CHAUFFEUR'S BLOOD TAMPERED WITH? Henri Paul, the chauffeur who was driving Diana and Dodi's limousine when it crashed, was responsible for the crash because he was driving too fast and blood tests showed he was drunk, police say. Paul was also killed in the crash.

Al-Fayed queries whether the blood tests were genuine. He argues there is no explanation for a high level of carbon monoxide in the blood and there are no remaining samples to prove through DNA tests that the blood was Paul's.

DIANA'S BODY EMBALMED Diana's body was embalmed in France three hours before being brought back to Britain. Although not an unusual practice, this would make an autopsy in Britain more difficult, al-Fayed says.

Furthermore, it would make render some tests, such as those for pregnancy, redundant. Al-Fayed also queries why Diana was embalmed again in Britain.

British police said embalming was carried out in accordance with French procedures to make Diana's body presentable on account of the injuries she had suffered.

MISSING VEHICLES The main unanswered question. Where is the missing Fiat Uno that collided with Diana's limousine before the crash? Every police report states the existence of the car but it has never been traced.

Al-Fayed also says five witnesses report seeing a ''fast dark'' car in the tunnel at the same time. Some say it was trying to slow down or get in front of the Mercedes.

Other witnesses describe seeing at least one motorbike that disappeared afterwards.

''THE COUPLE WERE ENGAGED'' Al-Fayed claims Dodi and Diana were planning to marry and his son had planned to present her with an engagement ring on the day of the car crash.

He says the couple had selected a ring from Repossi jewellers in Monte Carlo when the couple were holidaying there, and Dodi had picked it up on Aug 30, 1997.

He said he had spoken to the couple that night and they had both confirmed the engagement which they were planning to announce when they returned to London a couple of days later.

He believes her calls were monitored by Britain's MI6 security agency and the CIA. He claims the decision to kill them had to be made quickly before the engagement was announced.

However none of Diana's friends were aware of any impending engagement, although they knew Dodi was planning to buy her a ring, and some said the princess had told them the relationship was not serious.

Mohamed al-Fayed's press spokesman Michael Cole told a news conference at Harrods on Sept 5, 1997: ''What that ring meant we shall probably never know and if the planet lasts for another thousand years, I'm quite sure people will continue to speculate about its significance.'' DIANA PREGNANT? Al-Fayed has also claimed Diana and Dodi had both confirmed to him in telephone calls that the princess was pregnant.

Much of the speculation for this centred on a picture taken of Diana wearing a swimming costume on July 14, 1997, which commentators speculated suggested she might be pregnant.

That day she also told press gathered on the French south coast where she was holidaying at the al-Fayed villa that ''you're going to get a big surprise with the next thing I do''.

However she had not even started her relationship with Dodi at the time of the photo.

Again friends, family and associates dismiss the claim, saying she had not told them about it.

A post-mortem carried out by Britain's Home Office pathologist found no visible signs of a pregnancy.

A test on Diana's blood found in the wreckage of the Mercedes suggested she was not pregnant although experts said this could not be seen as conclusive.

REUTERS PD VV1845