A driver is wanted after a woman was killed in a hit-and-run in Western Sydney, with police appealing for public assistance.

The woman, believed to be aged in her 40s, was struck by an orange dual cab ute on Macquarie Ave in Penrith about 5.30pm on Thursday.

Vision from the scene shows the vehicle pausing briefly before driving off without offering help.

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Paramedics treated the woman but she could not be revived.

She is yet to be formally identified, but police believe she is a visitor to Australia rather than a citizen.

“She has been in the country approximately six months, although we have no family to confirm that,” said Superintendent Anthony Boyd.

Boyd urged any colleague or friend of the woman to come forward to assist with the investigation.

He also appealed to the driver to come forward, noting police have numerous witnesses and CCTV footage.

“We have very strong leads. If you were the driver of that vehicle, I suggest you come and meet with us,” he said.

“For somebody to strike a pedestrian, not stop and offer assistance, is very poor, abhorrent behaviour.

“From a driver of a vehicle to not even check on their welfare and continue on your journey for whatever reason is totally unacceptable in anyone’s book.”

Police have released photos of the ute and are urging the driver to come forward.

Police are also appealing to anyone with dashcam footage who was travelling on Macquarie Ave, Lemongrove Rd, or the Lemongrove Bridge in Penrith about 5.30pm on Thursday to contact Crime Stoppers.