Prince Charles Isn’t In a Hurry to Be King: He Will Only Say 'If I Succeed,' Not When

He is the longest-serving heir to the British throne in history, but Prince Charles is not in a hurry to be king.

Charles — who has worked in public life in support of his mother, Queen Elizabeth, for five decades — talks only about “if I succeed,” not when. Succession, of course, occurs only upon the death of his 92-year-old mother so it is not something he dwells on.

Instead, he has fully embraced his lifelong role as the Prince of Wales. “He’s one of the first people in the family to end up making the most of that role,” Prince Harry told the BBC’s Prince, Son and Heir: Charles at 70 last week.

Royal family portrait released in honor of Prince Charles' 70th birthday.
Royal family portrait released in honor of Prince Charles' 70th birthday.

Charles turns 70 today — a milestone that will be marked with a party held by the Queen at Buckingham Palace this evening. On Tuesday, the birthday was celebrated with a two new portraits of his sons, daughters-in-law and grandchildren, along with a series of new stamps.

At the heart of his public work is the Prince’s Trust, the organization he set up 42 years ago with his $10,000 severance pay from the Royal Navy. It has since helped more than 900,000 young people get int jobs, education and training.

For more on Prince Charles at 70, pick up a copy of this week’s PEOPLE, on newsstands Friday

“He still feels there are things he can do,” Dame Martina Milburn, head of the Prince’s Trust, tells People in this week’s issue.

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“He is as passionate about the Trust as he was when he first set it up,” says Milburn. “I see absolutely no sign of slowing up at all.”

Adds former royal staffer Dickie Arbiter, “There was no designated job for the Prince of Wales. He has created one with the setting up of the Prince’s Trust and has been interested in architecture and the environment and has set up charities that reflect those. He has a pretty full role in life.”