A West Sussex man has posted footage online of the moment a motorist drove onto a roundabout oblivious to the fact there was already a cyclist on it, knocking the rider off their bike.

The incident happened at the Redkiln Way roundabout in Horsham and was shot on a dashcam belonging to Mike Dearsley, who said it showed why cycling infrastructure physically separating cyclists from motorists is needed.

Last October, Mr Dearlsey tweeted that he had suffered a near-miss while riding his bike through the same roundabout.

Referring to the video Mr Dearsley posted yesterday, Mark Treasure of the Cycling Embassy of Great Britain, who lives locally, described the roundabout as a “big fast mess.”

The footage also attracted the attention of traffic police in the West Midlands, who have been widely praised for their innovative close pass initiative that has since been picked up by other forces across the UK.