The Newcastle City Hall clock will be set to midnight and chimes turned off as the council prepares to repair time-keeping after issues.
Newcastle council announced it would upgrade the historic clock and employ a heritage consultant to guide the repair.
It comes after a regular check-up from the council's mechanical and electrical services team identified a range of technical issues affecting the operation of the clock and chimes.
The clock will be set to midnight and chimes turned off while advice is obtained and subsequent permissions are sought from Heritage NSW.
City of Newcastle executive director city infrastructure Clint Thomson said the clock tower was an antique structure that needed to be handled with care.
"Newcastle City Hall's iconic clock tower has been a well-loved landmark at the heart of the historic Civic precinct since the building, designed by acclaimed architect Henry White, opened in 1929," Mr Thomson said.
Mr Thomson said due to the clock's age and significance, the repairs will be complex and "you can't rush in and fix it overnight".
"Given the state heritage significance of city hall and its associated clocks and chime, a heritage consultant will advise the most appropriate approach to repair, which will then need to receive approval from the relevant heritage authorities," he said.
The upgrade will be the latest investment into preserving the landmark building.
City of Newcastle invested $20 million into a large-scale conservation project on City Hall, which was delivered in stages and completed in 2021.
The completion of the exterior restoration works was celebrated with a visit from the Governor-General.
Conservation work was undertaken by Stone Mason and Artist Pty Ltd, who was responsible for the clock tower restoration.
