A man thought he'd spotted a UFO flying over London.

UFO in London?

UFO in London?

The quick-thinking guy captured a blue triangular object with silver ends in a cloudy sky and shared the footage online.

He said: ''I saw it fly above my head and just had time to pick up my 90x zoom camcorder to film.''

After viewing the footage on YouTube channel The Hidden Underbelly 2.0, many were left impressed and thought they'd seen alien life.

One user said: ''Great footage.''

Another asked: ''Did it just hover there? Or to outer limits?''

But others were not so convinced there was anything out of the ordinary about the object.

One commenter said: ''Looks like a toy.''

Another added: ''Looks like a balloon, honestly.''