“We are making sure that we are prepared. We’re ironing out all the kinks in the system to ensure that it is safe and reliable,” Haylen said.

Confirmation of the target date for the opening follows about 15 months of intensive testing and commissioning of the new infrastructure,including twin tunnels,driverless trains and stations,which is a key step towards gaining accreditation before passenger services begin.

Sydney Metro chief executive Peter Regan said it was targeting August 4 for the opening to give the public as much notice as possible,but if all the exercises and final testing were not completed in time,a later date would be announced.

The opening date for the new line under the heart of the city will also influence the start of a 12-month closure of the Bankstown line to allow it to be converted to metro trains’ standards,as well as a new timetable for Sydney’s rail network.

Haylen said the Bankstown line’s closure was “some months away”,but she reiterated that it would not happen until there was a high level of service reliability on the city-section of the metro line.

The second stage of the city’s expanding driverless train network has been known asMetro City and Southwest during seven years of construction. It is an extension of the existingMetro Northwest line,which opened in 2019 between Rouse Hill and Chatswood at a cost of $7.3 billion.

The two stages will form one line and be known as the M1 Northwest and Bankstown line when it opens to passengers. A metro train journey from Chatswood to the new Gadigal station near Town Hall in the CBD will take 13 minutes,while Chatswood to Sydenham will take 22 minutes.

The opening of the line before 5am on August 4,a day after the official ribbon cutting,will be slightly different to that forMetro Northwest in May 2019,when passengers filed through ticket gates less than an hour after then-premier Gladys Berejiklian cut the ribbon on the project on a Sunday.

Minns has previously paid credit to the previous Coalition government for its work on the mega project,and said that Berejiklian and other former premiers will be invited to the opening of the extended metro line.

Since “on-track dynamic train testing” of the main new section started in April last year,about 9800 hours of a total of 11,000 hours of required testing has been completed along the 51.5-kilometre line from Tallawong to Sydenham.

Theopening of the final part of the Metro City and Southwest project between Sydenham and Bankstown has been delayed until late next year due to difficulties converting an existing stretch of rail line to metro train standards.

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