Police are appealing for information after a taxi driver was robbed this morning in Woolloomooloo.

Police have been told about 6am (Thursday 22 June 2017), a 75-year-old man was driving his taxi in the Sydney CBD when two male passengers entered the vehicle.

The 75-year-old man drove the two men around Woolloomooloo before he was directed to stop on Harmer Street and threatened by the men with a firearm.

The driver was dragged from the car by the men and punched.

The two men left the scene in possession of cash and a bag, which were both stolen from the taxi.

The firearm was left in the taxi by the two men and was found to be a replica firearm bound with bright blue tape.

Officers from Kings Cross Local Area Command are investigating the incident and wish to speak to two men who may be able to assist with inquiries.

The first man is described as being in his late teens or early 20s and about 172cm tall. He was wearing a black hooded jumper and had blue or green paint on his face.

The second man is described as being in his late teens or early 20s and about 180cm tall. He was wearing a black hooded jumper.