A video published on Sunday by the media center of Islamic State purported to show images and last statements of nine of the people who took part in the Paris attacks that killed 130 people on Nov. 13.
Reuters could not independently verify the authenticity of the footage, which showed the men delivering anti-Western diatribes and concluded with an apparent threat to attack Britain.
The French Foreign Ministry declined to comment on the video. There was no immediate comment from the prime minister's office, and Reuters was not immediately able to reach officials at the Interior Ministry.
A spokeswoman for the National Security Council at the White House had no comment.