Terrifying moment Sydney school bus nearly causes major crash

Video has emerged of a school bus driver neglecting basic road rules and subsequently putting the lives of around 20 young children he was taking to school in jeopardy.

In astonishing footage recorded by a nearby CCTV camera on Thursday morning, the driver can be seen pulling out in front of a semi-trailer truck on a busy Sydney motorway.

The truck, with little to no time to react, is only just able to brake - but it was also forced to jack-knife in order to avoid going into the back of the bus with force.

The truck then spins out, sending plumes of smoke and blocking off a lane - all of which occurs while the bus continues its commute to the local school.

However other motorists flagged the bus down and called police, who have now launched an investigation.

Watch the moment in the video above.

Newshub.