A cyclist has been critically injured in a hit-and-run on a busy Sydney road.

Police say a red car and a pushbike rider collided on Spit Rd in Mosman about 5.15am on Sunday.

The rider was treated by paramedics at the scene before being taken to Royal North Shore Hospital in a critical condition.

Know the news with the 7NEWS app: Download today Arrow

The car did not stop and fled the scene.

“Police from the Crash Investigation Unit examined the scene and have commenced an investigation,” police said.

The bike, a helmet and a pair of cycling cleats were left behind at the scene.

Anyone with any information has been urged to come forward.

NSW premier calls for calm and royal commission after Bondi attack

3 min read

Major NSW highway closes as truck with lithium-ion batteries catches alight

1 min read