NSW truck drivers escape serious injury

Two drivers have escaped major injuries after two semi-trailers travelling in the same direction collided, sparking a large truck fire on a busy NSW motorway.

A 38-year-old driver was taken to hospital in a serious condition after one of the semi-trailers went up in flames on Thursday morning on the M1, near Mount White.

A NSW Ambulance spokeswoman said he was taken to Royal North Shore Hospital where he remains in a stable condition after sustaining head injuries as well as burns to one of his arms.

The other male driver only sustained minor injuries.

Motorists travelling northbound on the highway continue to face delays however two northbound lanes and one southbound lane have opened on the southbound side of the roadway.

Fire crews are still working to clean up canola seed and a diesel spill.

Meanwhile, the Great Western Highway has been closed westbound near Lithgow due to another truck incident.