A truck driver who ploughed a car for hundreds of metres down a Sydney highway says he had no idea the small sedan was caught under his bull bar.

Dashcam footage shows a woman in a white sedan veer in front of the semi-trailer on the Hume Highway near Ingleburn, in Sydney’s south-west.

When the two vehicles collide, the car rotates and becomes lodged under the truck’s bull bar before it is dragged hundreds of metres down the highway.

Shocking footage of a truck, dragging a car on one of Sydney’s busiest motorways has emerged online. #9News pic.twitter.com/bED0ZSJx1m

— 9News Sydney (@9NewsSyd) February 16, 2017

The truck driver, known only as John, said he didn’t know the car was right under his nose.

“[I] didn’t know the car hit my truck, [I] thought a wheel bearing went and was trying to find a safe spot to pull over,” he told the Nine Network.

As John pulls over to the left lane to check his tyre, the white car is seen scraping against the guard rail with the woman trapped inside.

The woman was issued with a “small fine”, Nine reported.