Motorcyclist killed after collision with truck

Police are investigating after a motorcyclist was killed after colliding with a truck in Sydney's southwest.

Police said the crash had taken place at about 1.30pm (AEST), when the rider collided with a cement truck on Cowpasture Road in Abbotsbury.

The truck driver is understood to be unhurt and was taken to hospital for drug and alcohol testing.

The motorcycle rider has not been formally identified.

Two of three northbound lanes are closed along the Horsley Drive from Cowpasture Road, following the accident.