Princess Diana asked a priest if she could marry Dodi Fayed in a church.
The Princess of Wales approached Father Frank Gelli shortly before the tragic car crash in 1997 which killed them both, and he believes she may have been seeking Christian approval to marry the 42-year-old Muslim man.
She wanted to know if it was possible for two people of different religions to marry. I told her it was.
"As we spoke her telephone rang. It was obviously Dodi. Her eyes lit up. As she was leaving she asked me if I would be able to perform the service when she got married. Her love was obvious."
Frank, who was a curate of St Mary Abbots church in Kensington, West London - close to where Diana previously lived at Kensington Palace - is convinced the pair would have tied the knot if they had not died in Paris 20 years ago.
He said: "I feel sure that if Diana and Dodi had not been killed, they would have married."
The priest also revealed Diana had started attending the church and used to inconspicuously pop in and sit at the back.
He told the Sunday Express newspaper: "Princess Diana was a wonderful, caring philanthropist.
"She would come sometimes into the church and sit at the back and pray."
It is also thought Dodi's father, businessman Mohamed Al-Fayed, was confident the couple would get married.
A source recently said: "Mohamed believes they were in love and were going to announce their engagement in London the day after the tragedy.
"He will never get over the death of his son, or that of the Princess - because of the love he had for both."
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