An 18-year-old motorcyclist was seriously injured in a crash with a car in the early hours of Wednesday.

The motorcyclist was headed west when he was in collision with a car travelling in the opposite direction.

The teenager was in stable condition at King Edward VII Memorial Hospital on Wednesday. No further details about his condition have been released.

The driver of the car, a 68-year-old Paget man, was treated for minor injuries and discharged.

A 27-year-old Warwick man and 19-year-old Devonshire man who were passengers in the car were uninjured.

Traffic diversions were set up for about three hours while police examined the crash scene.

Police have appealed for witnesses to the crash.