The sign outside the Fyshwick post office.

The sign outside the Fyshwick post office. Photo: Supplied

A Canberra post office was closed on Monday following a burglary on Sunday night.

A sign was placed on the door to the Fyshwick post office on Townsville Street on Monday, alerting customers to a robbery at the business.

An Australia Post spokeswoman confirmed the Fyshwick post office was burgled, and said it would likely reopen late on Monday afternoon.

The spokeswoman said ACT Policing was investigating the incident and Australia Post staff are cooperating with officers.

A police spokesman confirmed the incident but classified it as a burglary and not a robbery.

The incident was reported to police about 6.30am on Monday, and occurred some time after 8pm on Sunday.

A sign on the post office door apologised for any convenience caused and stated the office would remain closed until further notice.

Anyone with information regarding the burglary can contact Crime Stoppers on 1800 333 000.