Britain's Prince Charles kisses his bride, Princess Diana, on the balcony of Buckingham Palace in London, after their wedding. Photo/icpress

British police have found "no credible evidence" to reopen investigations into the deaths of Princess Diana and her friend Dodi al Fayed in a Paris road crash in 1997.

London's Metropolitan Police (MET) had said in August that they were assessing new information about the deaths of Diana, Dodi and their driver.

Media reports at the time said the MET had been passed allegations that a member of the British military had caused the deaths.

"There is no credible or relevant evidence to support a theory that such claims had any basis in fact," Rowley said in a letter that the British broadcaster said it had seen. Rowley added that the MET would not reopen any criminal homicide investigation or refer the matter back to the coroner.

Diana, Dodi and their chauffeur, Henri Paul, were killed when their car crashed in a road tunnel while pursued by photographers after the couple left the Ritz hotel in Paris on Aug. 31, 1997.

Dodi's father, Mohammed al Fayed, the former owner of Harrods department store, in 2008 said he was dropping his 10-year campaign to prove the couple were killed on the orders of the British establishment, for the sake of Diana's sons William and Harry.

The untimely death of Diana, who divorced heir-to-the-throne Prince Charles in 1996, sparked an outpouring of public grief that culminated in huge crowds lining the streets of London for her funeral.

A Royal spokesman said there would be no comment.

The MET is due to make a formal statement on the matter on Tuesday.