I just think it's important, particularly as I get older, to think about the journey that's coming next

Prince Charles

But a spokesman for Charles said he did not believe that that was a hint about his future.

"It's a statement saying 'I'm not going to answer that question'."

The prince himself, visiting a fete near his Highgrove home on Saturday, told reporters to leave him alone.

Since his marriage to Diana, Princess of Wales, ended in 1996 with admissions of adultery on both sides, St James's Palace has maintained that the heir to the throne had no intention of marrying divorcee Mrs Parker Bowles.

Public kiss

But the couple shared their first public kiss last week when the prince pecked Mrs Parker Bowles on the cheek as he arrived as her guest at a party.

Any marriage between the pair would pose considerable difficulties, not least to the Church of England since Mrs Parker Bowles is a divorcee.

The BBC's Royal correspondent Nicholas Witchell said the question of re-marriage is by far the most sensitive issue facing Prince Charles.

"In the past the heir to the throne has indicated that he has no intention of re-marrying," he said.

But in this interview Prince Charles' answer was ambiguous.

"His failure to rule out a marriage to Mrs Camilla Parker Bowles, may be interpreted as a sign that such a step is not now viewed as inconceivable," the royal correspondent said.

Privacy appeal

In the interview Prince Charles also appealed for Diana and his sons, princes William and Harry, to be left alone.

"The truth is that the children mind about the way in which she is dealt with," he said.

"It must be quite difficult for them, I think.

"I wish people could just let her soul rest in peace without all these constant reminders."

Charles added of the teenagers: "They are terrific, and I am very lucky to have them."