British Prime Minister Boris Johnson has joined the quick-video world of TikTok, promising "behind-the-scenes insight" into the ongoings at his Downing Street office.

The prime minister's video appeared as the first clip on the new "10downingstreet" account on Tuesday, racking up more than half a million views and tens of thousands of followers within hours.

"Hi folks, this is Boris Johnson here launching the Number 10 TikTok site," he said.

"You won't necessarily catch me dancing on this site, but you will have all sorts of stuff about what we're doing to deliver on our priorities, deliver for you on our agenda of uniting and leveling up our country. You'll get all sorts of messages and content that you might not get if you're looking at Instagram or Snapchat or Facebook – Twitter, LinkedIn and all the other stuff."

Thousands of comments flooded the video, which was published at around midday.

"The comments are gonna be turned off so quick," wrote one. "Theresa would have danced. 0.001/10 Boris," replied another.

Former Love Island contestant Hugo Hammond, meanwhile, posted, "This has to be a joke," along with a laughing emoji.

The prime minister has accounts on Facebook, Twitter, Instagram and Snapchat, with millions of followers across those platforms.