Western Sydney's City Deal, announced on earlier this week, is a "game changer" for Australia's fourth largest economic region, and could mean 200,000 new jobs, says the Property Council of Australia (PCA).

The first large-scale City Deal, announced by prime minister Malcolm Turnbull and NSW premier Gladys Berejiklian, will bring together eight local government areas and sets out a roadmap for growth and development across a large part of Western Sydney.

Announcing the agreement, Turnbull said the City Deal represented an "historic change" for Western Sydney.

"For the first time, working together, we are putting a plan and the infrastructure in place first,' PM Turnbull says.

The City Deal promises to deliver a North South Rail Link from St Marys to the new Badgerys Creek Aerotropolis via the new Western Sydney Airport. 

The Property Council's executive director in NSW, Jane Fitzgerald, says the City Deal "demonstrates a fair dinkum commitment which, if implemented well, will improve transport, liveability, housing supply and long-term collaboration across Western Sydney".

The City Deal predicts 200,000 jobs will be created, and Fitzgerald says the investment in rail for the region will not only service the new airport but also develop "orbital communities" which will be "critical to future housing supply".

According to the Greater Sydney Commission, Sydney needs 725,000 additional homes between 2016 and 2036. Fitzgerald says accelerating the delivery of housing in nine local government areas will help the Commission achieve its targets.

The City Deal also provides industry with the confidence to invest. "A long-term agreement means all sectors know what government policy is coming over the horizon and can invest accordingly," Fitzgerald adds.

Both governments have committed to having the rail line operating when the Western Sydney airport opens.

In addition, $100 million has been committed to progress a full business case for the remainder of the line. 

The Aerotropolis will be kick-started with 114 hectares of Commonwealth-owned land at North Bringelly, which the prime minister says will "form the nucleus of a world-class precinct of knowledge intensive industry and learning".