The Prince of Wales is in no rush to become king because he fears being monarch will be a form of prison, according to one of his officials.
The unnamed individual is quoted in a profile of Prince Charles published in Time magazine which features the prince on its front cover.
Time spoke to 50 of the prince's friends and associates.
Prince Charles will represent the Queen at next month's Commonwealth heads of government meeting in Sri Lanka.
For decades, as heir to the throne, the Prince of Wales has founded charities and spoken out on many issues.
In the coming years, he will have to do more of his mother's work as she, now 87, does less.
The Time profile said the prince took on extra royal duties "joylessly" and, far from "itching to assume the crown", he was already feeling its weight and worrying about its impact on his current role.
The writer also stated that the Queen's heir was impatient to get as much done as possible before, in the words of one of his aides, "the prison shades" close.
Prince Charles, who does not comment on his accession, was quoted as saying he had always had this "extraordinary feeling" of "wanting to heal and make things better".
The author of the article said the prince sat down with the magazine "to discuss his hopes - and profound concerns - for the future".
The interview was published as official photographs for the christening of Prince George were released.
They showed the Queen with three future kings - the Prince of Wales, the Duke of Cambridge, and Prince George.
It was the first such image since the christening of the future Edward VIII in 1894, with his father George V, grandfather Edward VII and great-grandmother Queen Victoria.
The Prince of Wales and the Duchess of Cornwall will tour India before the Commonwealth summit.
Commonwealth leaders meet every two years and the Queen has attended every one since 1973.