Princess Diana's stepmother told an inquest today she thought Diana and Dodi al-Fayed were "madly in love" and planning to wed before their deaths in a 1997 Paris road crash.

Countess Spencer, daughter of romantic novelist Barbara Cartland, ended an hour of testimony to London's High Court by pleading with the judge, jury and lawyers to do their utmost to solve any mystery over the deaths.

Dodi's father Mohamed al-Fayed, owner of the Harrods luxury shop in London, alleges Diana and his son were killed by British security services on the orders of Prince Philip, Queen Elizabeth's husband and Diana's former father-in-law.

Fayed believes her killing was ordered because the royal family did not want the mother of the future king having a child with his son. He alleges Diana's body was embalmed to cover up evidence she was expecting a baby.

"Diana was madly in love with (Dodi)," said the countess, dressed in a black hat with a veil drawn back off her face.

"She said she had never been so happy for years. That was the moment I really felt it was highly likely that she and Dodi would get engaged and then get married."

Asked if Diana had ever mentioned being pregnant, the countess said: "Diana was brought up in a quite old-fashioned way. I don't personally believe she would have considered it."

She dismissed allegations of bad blood between Diana and Prince Philip.

Sign up to our free newsletters

Get the best updates straight to your inbox:
Please select at least one mailing list.

You can unsubscribe at any time by clicking the link in the footer of our emails. We use Mailchimp as our marketing platform. By subscribing, you acknowledge that your information will be transferred to Mailchimp for processing.