Lucy Turnbull's resolve to boost economic development in Sydney's west is challenged by the state government's own figures showing the east will remain the epicentre of jobs growth over the next two decades.
The chief of the agency charged with reshaping the city, the Greater Sydney Commission, said Australia's most populous city should be "reimagined" as three great cities – what she has termed the Eastern Harbour City, Central Parramatta River City and the Western City near the proposed new airport at Badgerys Creek.
Speaking on Thursday, Ms Turnbull said dividing Sydney into three cities was needed because of the forecast population growth.
"Sydney's population is growing rather rapidly at the moment. In 20 years' time we will have a population of 6.2 million – we have 4.6 [million] now. And demographers say by 2056 we will be a city of 8 million people," she said.
"We can't expect all of the jobs growth to happen in what we call ... the eastern city. The jobs growth and the opportunities have to be well distributed though our city so we do not become congested."
However, her long-term aim to create three hubs is challenged by state government forecasts.
While the population of western Sydney will surpass the east's by 2038, the government expects the majority of jobs will continue to be in the east, "resulting in a continued imbalance between where people live and work".
And by 2041, it expects 680,000 more jobs will be in the east than in the west.
The forecasts are contained in a summary of the business case for the second stage of Sydney's new $20 billion-plus metro rail line due for completion in 2024.
They form part of the rationale for Australia's biggest rail project running from Rouse Hill in Sydney's north west to Chatswood, and onto the CBD, Sydenham and Bankstown in the west.
"It is imperative that the Sydney CBD continues to be Australia's premier commercial district and build on its strengths," the business case summary says.
"The Sydney CBD has 10 times the number of jobs than any other centre in Sydney."
The government has highlighted Sydney's so-called global economic corridor in which "knowledge jobs" are clustered. It arcs from Sydney Airport, the CBD to Chatswood and the north west, and takes in Parramatta and Sydney Olympic Park.
But Ms Turnbull said the population growth in and around Parramatta was higher than any other part of Sydney, and the area would have "huge investment" from the public and private sectors over the coming years.
"Sydney's momentum – population and economic – will be moving westward and that is inevitable, so we need to recognise that in our strategic planning," she told ABC Radio.
"It is not just about the airport [planned for Badgerys Creek] – the airport is an important anchor. It is all about the other businesses that will locate there."
The commission has tagged an area spanning from greater Parramatta to Olympic Park as "GPOP", and expects it to become "the connected, unifying heart" of Sydney.
The former Sydney lord mayor said the thinking about planning Sydney needed to revolve around creating a "30-minute or even a 45-minute" city for the most number of people as possible
"We need to reconceptualise how we see our city rather than just being the eastern CBD and western Sydney," she said.
