The full inquests into the deaths of Diana, Princess of Wales and Dodi Fayed are to be delayed until October.
The inquest will take place after the 10th anniversary of the crash
Coroner Lady Butler-Sloss wanted a May hearing but lawyers for Mohammed Al Fayed, Dodi's father, requested more time to allow them to prepare.
Mr Al Fayed alleges the August 1997 Paris road crash which claimed the couple's lives was part of a secret plot by the British establishment.
However, the coroner said she had not heard evidence to support the theory.
In a written decision, Lady Butler-Sloss, the deputy royal coroner, said the inquests will take place "on or about" 1 October.
The hearings are expected to last between four and eight months.
Harrods department store owner Mr Al Fayed won a High Court ruling that the inquests should be heard before a jury.
The decision overturned a decision by Lady Butler-Sloss that she would sit alone.
But at a later pre-inquest hearing, the coroner said she would not allow the jury to hear Mr Al Fayed's claims unless his legal team could present evidence to back them up.
A three-year inquiry conducted by former Metropolitan Police chief Lord Stevens concluded that Princess Diana had died in a tragic accident and that there had been no conspiracy and no cover-up.
"There are a large number of serious allegations being made," Lady Butler-Sloss said.
"At the moment, there is not a shred of evidence given to me about these allegations."
Michael Mansfield QC for Mr Al Fayed indicated that his legal team needed access to documents collected by the Metropolitan Police.