Britain's Prince Charles considered jilting his first wife, Princess Diana, at the altar.

Britain's Prince Charles

Britain's Prince Charles

The 66-year-old royal is reported to have been "desperate" to call off his wedding to the late Princess before they tied the knot in 1981.

The claim is made in a new unauthorised biography 'Charles: Heart of a King' by Catherine Mayer, who alleges that the heir apparent changed his mind about marrying the future Princess after discovering she was "not the jolly country girl he had assumed".

According to the Daily Telegraph newspaper, Charles told his closest confidant at the time: "I can't go through with it, I can't do it."

Andrew Morton, Diana's biographer has also spoken of the blonde beauty's desire to pull out of the marriage, claiming she told her sisters Sarah and Jane: "I can't marry him, I can't do this, this is absolutely unbelievable."

However, her siblings are said to have told her she had to go through with the nuptials as "your face is [already] on the tea towels".

Like Charles, Catherine claims Diana had no idea her future spouse was being "coaxed to the altar."

The pair - who had two sons, Prince Harry, 30, and Prince William, 32, were married until their divorce in 1996, following Prince Charles' affair with his current wife the Duchess of Cornwall.

Princess Diana passed away the following year from injuries she sustained in a car crash in Paris.