The planned opening of a $21 billion driverless metro line under the Sydney city centre has been thrown into disarray with regulators yet to sign off on the start of passenger services.
The latest piece in Sydney's Metro network - Australia's largest public transport project - was due to open on Sunday, but NSW Transport Minister Jo Haylen said more time is needed for safety approval.
"The target date was always a target date, unfortunately, we're not going to quite make it, but we are very close," she said when announcing the delay on Tuesday.
The Office of the National Rail Safety Regulator is yet to give the go-ahead for the route to start carrying passengers from Chatswood, in Sydney's northwest, under the harbour and the city centre.
Outside the entrance to Martin Place train station, the Sydney Metro blue t-shirts of two men encouraged the public to ask them about the line as news spread of its delayed opening.
But not even the transport minister can answer the question everyone wants to know: when it will open.
"Our absolute priority is a safe and reliable route," Ms Haylen said.
She refused to nominate a new date.
The trains have been tested, the operator is ready to run them and changes have been made to bus timetables to feed commuters into the network, Ms Haylen said.
Changes to bus timetables will still begin on Sunday, despite the metro's delayed opening.
"We'll make sure that those journeys are smooth ... but also that there are other services that they can connect to," Ms Haylen said.
Multiple factors contributed to the delay.
"One of those of course is the incident that occurred on the northwest, as well as industrial action," Ms Haylen said.
The northwest section of the line, beginning at Tallawong, near Blacktown, left passengers stuck for hours earlier in July.
The Fire Brigade Employees Union also put a since-lifted ban on emergency management exercises amid a stoush over funding.
State secretary Leighton Drury said it was firefighters' job to plan for worst-case scenarios.
"But if we don't have the things we need to get that job done then things turn ugly quickly,'' he said.
"Industrial action from our members is not the cause of delay here."
The transport minister's announcement brought reporters to a platform deep underground the otherwise inaccessible Martin Place station to confirm it would remain closed to the public for longer.
Opposition leader Mark Speakman was locked outside like everyone else when he told reporters the metro had been planned and designed by the former coalition government.
"Now Labor can't even get the opening date right," he said.
The rail safety regulator said on Monday it was assessing the opening of the line's extension as quickly as possible.
"There are still several critically important activities to be completed this week, such as emergency and evacuation exercises," it said.
