Police are appealing for information following the assault and armed robbery of a taxi driver at Campsie on the weekend.

About 3:25am on Sunday 3 November 2013, a man was driving a taxi along Beamish Street when he was flagged down by a man who got into the front passenger seat of the taxi.

During the incident the man threatened the driver with a sharp object, demanded cash and punched him in the head a number of times.

The taxi driver stopped on South Parade and turned the taxi off before running away. He was then chased by the passenger and contacted police. A small amount of cash was stolen during the incident.

Police from Campsie Local Area Command attended the scene and despite a search of the area were unable to locate the man.

The taxi driver, a 40-year-old man, was treated by NSW Ambulance Paramedics and taken to Canterbury Hospital for further treatment to facial injuries.

Detectives have released CCTV images of a man who they would like to speak to and believe may be able to assist with their inquiries.

The man depicted in the images is described as being of Asian appearance, 50-55 years old, about 160cm tall with a slim build, short dark brown hair and wearing a grey jacket, collared t-shirt and long grey pants.