Britain's Prince Harry performed a cabaret at Queen Elizabeth's birthday dinner.

Prince Harry

Prince Harry

The 31-year-old royal joined forces with ventriloquist Nina Conti to act as her dummy for the performance which had the whole room in stitches during a celebration at Windsor Castle last week.

A source told HELLO!: "It was genuinely brilliant. He must have been working on it because he had to do the actions in time with her speaking. It was intensely funny because he was so good."

The monarch was joined by 71 of her closest friends and family members for a formal dinner, arranged by her son Prince Charles, in the Waterloo Chamber.

Meanwhile, Prince Harry recently admitted he sees the Queen as a boss first and a grandmother second.

In an interview for the 'Elizabeth At 90 - A Family Tribute' documentary, he said: "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.

"People always ask, 'Do you ever feel as though you're following in her footsteps? And yes, that's exactly what we are doing. There is nowhere on this planet I can think of that she hasn't been in the last 90 years.

"She's been everywhere, and sometimes that's quite hard because you go to a place where she hasn't visited for 20, maybe 15 years, and you think to yourself, how can I ever fulfill this huge expectation that comes with her and being a member of her family?"