Property Council Western Sydney Regional Director Ross Grove said it was a long-awaited step that will help ease congestion and support Western Sydney's growth.
"The signing of construction contracts marks an important milestone in delivering the infrastructure backbone the region needs as Western Sydney International Airport nears completion," Mr Grove said.
"With the airport opening next year, the M5 will become a critical connection point - especially for the thousands of trucks moving freight between the Moorebank Intermodal and the wider motorway network.
"This upgrade is about more than relieving congestion. It's about unlocking productivity and enabling the next phase of Western Sydney's economic development."
The project includes a new toll-free bridge over the Georges River and an underpass at Moorebank Avenue to improve safety and traffic flow - changes set to benefit more than 2,500 trucks and thousands of commuters who rely on the corridor every day.
Mr Grove said the Property Council had long advocated for upgrades to freight and logistics infrastructure to keep pace with the region's rapid growth.
"We commend both governments for moving this project forward, and we'll continue to push for the road investments our region needs to unlock growth in homes and jobs."
