Princess Diana received a stern warning from a policeman the night before her engagement to Prince Charles.

In the book “Diana: Her True Story,” the Princess of Wales shared what happened with royal biographer Andrew Morton. After leaving her flat for the first time, a policeman told the mom of two that it was the last time that she could enjoy her freedom. After all, she will soon get engaged to the future King.

Princess Diana said that hearing the warning felt like a sword went into her heart. But during her engagement the next day, Princess Diana smiled from ear to ear in front of the cameras. It was only years later that her real thoughts and feelings at that time were unveiled.

“I was brought up in the sense that you know, when you got engaged to someone, you loved them. The most extraordinary thing is we had this ghastly interview with day we announced our engagement and this ridiculous ITN man said, ‘Are you in love?’ I thought what a thick question so I said, ‘Yes, of course, we are,’ in the sort of Sloane Ranger I was,” she said.

To Princess Diana’s surprise, Prince Charles gave a different answer to the question. When asked if he was in love with the Princess of Wales, the heir to the throne said, “Whatever love means.”

Morton revealed in his book that this wasn’t actually the first time that Prince Charles told his wife the statement. According to the royal expert, Princess Diana immediately said yes to Prince Charles when he asked her to marry him.

But during the privacy of that moment, Prince Charles also said: “whatever love means.” “So you have to ask yourself, did he really have any kind of genuine feeling for Diana or was she, as she felt herself, a sacrificial lamb… producing an heir and a spare and then being discarded?” he told Fox News

Prince Charles and Princess Diana Prince Charles and Princess Diana are pictured attending a centenary service for the Royal College Of Music on Feb. 28, 1982 at Westminster Abbey, London. Photo: Fox Photos/Hulton Archive/Getty Images