Online footage of the incident, which occurred earlier this month during an afternoon news bulletin on the privately held REN TV channel, is being avidly viewed in both Russia and the United States.
In the footage, Tatyana Limanova, an award-winning senior newsreader at the channel, can be seen briskly reading out an item about how Russian President Dmitry Medvedev has just assumed the rotating chairmanship of the Asia Pacific Cooperation organisation.
She is then heard to say that the post "has (previously) been held by Barack Obama" before mechanically and unambiguously raising her left arm and showing the camera her raised middle finger in an offensive gesture that is sometimes known as "flipping the bird."
The channel, which goes out to 120 million people across Russia, has declined to comment. But sources close to it have tried to defuse the row by claiming that the newsreader had believed she was off camera at the time and merely providing a voice-over for a report. According to the same storyline, the rude gesture was intended for studio technicians who had been trying to put her off her stride.