OUR reader Krzysztof Dreczkowski has filmed this remarkable footage.
Krzysztof has already sent us pictures of a UFO he spotted over Corby Boating Lakes - click here for that shot.
And he also sent us pictures of a mystery object spotted over fields in Lincolnshire - click here for those pictures.
This time he spotted this strange UFO over Westminister Abbey in London at the end of December. Look to the left of the video near the trees for the mysterious white light.
UFOs hold special interest for Krzysztof because he is part of a UFO organisation in Poland, his homeland.
Can you help identify his latest enigma? Make sure you register on our by clicking the blue Register button at the top of the page and let us know what you think.