Britain's Prince Harry would love to believe that he "is funnier than his grandmother" Queen Elizabeth.

The 27-year-old monarch gets a kick out of his family's sense of humour.

Although the Royals adhere to strict codes of propriety while out in public, Harry admits that the clan lets loose in intimate settings.

"[Queen Elizabeth] is very funny, but I think she gets it from my grandfather. They are very funny together," he told UK newspaper The Telegraph. "My family is the same as any other family when it comes to humour behind closed doors, though I'd like to think I was funnier than my grandmother."

Prince Harry has just completed his Diamond Jubilee tour of Commonwealth countries Belize, Jamaica and the Bahamas. This 10-day trip impacted him profoundly.

"I tell you what, it's been an emotional trip," he said. "I'm absolutely exhausted but the warmth of the reception that we've received from every single country that we've been to has been amazing."

Harry is eager to be home so that he can turn his attention toward his military duties. Serving his country is of deep importance to the young Royal.

"I'll do what's asked of me. You can't sit there with a stiff upper lip and not get involved," Harry declared. "I'm in a very privileged position, so I'll use my title to help out where I can, but at the same time, we've [my brother Prince William and I have] got our military careers, and that's what we'll continue to do."

"I will help out with my grandmother [with civic duties] whenever [The Queen] needs me, but I have this [military] job that does suck up a lot of my time, and that's the number one for me."

Prince Harry is expected to serve in Afghanistan later on this year.