Police investigating the armed robbery of a post office in North Revesby have released CCTV as part of their ongoing investigation.

About 10.30am on Friday 21 March 2014, two men armed with kitchen knives entered the post office on Beaconsfield Street.

The men, who had their faces concealed, threatened staff before fleeing empty-handed.

They were last seen getting into a car described as being a white two-door Honda Civic hatchback, possibly an imported Type R (EP3), with red and white NSW number plates.

No one was injured during the robbery.

Police from the Metropolitan Robbery Unit are investigating the incident and the possibility the same offenders have committed similar offences in south-western Sydney.

They have released CCTV of the post office robbery and are appealing for anyone with information to come forward.