Prince Harry views the Queen more as his boss than his grandmother, he has told a documentary to mark the monarch’s 90th birthday.

Harry, who was interviewed for the BBC’s Elizabeth At 90 – A Family Tribute, discusses the respect he has for the royal matriarch, according to this week’s Radio Times.

“I still view her more as the Queen than my grandmother. You have this huge amount of respect for your boss and I always view her as my boss – but occasionally as a grandmother,” the Prince said.

Britain's Prince HarryBritain’s Prince Harry (Kirsty Wigglesworth/AP)

The programme, which will be broadcast on BBC One on April 21, the Queen’s birthday, also sees the Princess Royal describe the monarch’s mixed feelings about becoming the nation’s longest reigning sovereign.

Anne said: “Don’t forget there’s a very double-edged sword. People tend to forget when she passed the longest reigning monarch, that was only because her father died so young.

“So you know for her that’s a very mixed blessing, and you know it’s a record that she would much rather not have been able to pass.”

Prince Harry at the Royal Variety Performance Prince Harry at the Royal Variety Performance (ITV)

The Queen’s cousin Princess Alexandra reveals that during the Second World War, a kind Princess Elizabeth gave her hand-me-down outfits when it was difficult to buy clothes due to rationing.

The documentary also features home cine movies shot by the monarch and the Duke of Edinburgh through the ages.

The programme’s director John Bridcut describes the Queen’s camera work as “very steady”. Much of the footage has never been seen publicly before.

The Queen, who turns 90 this monthHer Majesty The Queen (Anthony Devlin/PA)

Mr Bridcut said the insight into Windsor family life showed how the Queen, Philip and their children used lots of teasing, rather than overt physical contact, to show affection.

Elizabeth At 90 – A Family Tribute is broadcast on April 21.