Sydney commuters are being told to "brace for chaos" as unions claim thousands of bus trips will be cut across the city on Monday.
The cancellations cover regions north, northwest, south and southwest of downtown Sydney, including the Northern Beaches, eastern suburbs and inner west.
Peter Grech, tram and bus division president of the Rail, Tram and Bus Union, said the state government's privatisation of the bus network had left it struggling to attract and retain drivers.
"Commuters should brace for chaos at our bus stops from Monday as the NSW government axes thousands of trips in an attempt to deal with the fallout of its bus privatisation," Mr Grech said.
"We're already seeing incredibly large queues at bus stops, but that will get much worse on Monday when services are axed, many people return to work and kids return to school."
While the union is laying the blame at the state government's feet, they are urging commuters to show respect to drivers.
"Bus drivers understand passengers' frustration because we're frustrated too," Mr Grech said.
"It's important to remember that it's not the drivers' fault that our bus services are being so poorly managed."
The warning from the union marks another stage in its long running spat with the Perrottet government, which has seen multiple strikes and union actions.
Transport officials forced the city's train network to shut down in February last year, locking out train drivers in the middle of industrial negotiations with unions.
