Prince William and Kate Middleton rib each other in 'unexpected' trailer for new YouTube channel

Prince William and Kate Middleton may not have been the royals grabbing the most headlines lately, but it appears the Duke and Duchess of Cambridge aren't giving up the spotlight that easily. 

The future king of Britain and his wife delighted and surprised fans with the unveiling of their "unexpected" YouTube channel, which they promoted with a trendy trailer showing a more playful side to the pair. 

"Be careful what you say now, because these guys, they're filming everything," William says at the start of the fast-paced clip, pointing to cameras. 

"I know!" Kate laughs nervously. 

The brief 25-second-clip features choppy editing and uncharacteristically modern background music, with Kate and William seemingly looking to target a younger demographic with their new social media platform. 

Between shots of the pair appearing at various engagements that see them shearing sheep, flying in a helicopter, doing archery and serving up food for charity, there are glimpses at the couple's dynamic as husband and wife. 

"You don't have to roll your 'r's," Kate tells William during filming of a special St Patrick's Day message. 

"Do you not roll it?" William replies, as Kate shakes her head "no". 

The clip immediately trended on YouTube, and was flooded with comments from well-wishers who were overjoyed to see the couple's debut on the video sharing site. 

"Well this was unexpected - good luck guys!" one fan wrote. 

"Super excited for this historical venture!!!!" said another.

"It’s a wacky world we live in when the future king and queen are YouTubers," offered a third. 

Meanwhile, it didn't take long for fellow YouTubers to speculate about what kind of video content they could expect from the Duke and Duchess - joking that perhaps the royals would join in on some of the sites best-known trends. 

"Kate, drop a 'what's in my bag' video PLEASE," one comment read. 

"Ok can we have a house tour please - I mean a castle tour? How about 'a day in the life of a Duchess'? How cool it is to see behind the scenes of your royal engagements," said another. 

"Imagine if they made clickbaity videos like: 'OMG, never go to Elizabeth's room at 3 am (Scary) 100% Not Clickbait'," mused a third.