An industrial fight between the NSW government and workers plunged the country’s largest city into traffic chaos on the day it reopened to the world, prompting the Prime Minister to turn the brawl into an election issue.

The Perrottet government shut down all Sydney and intercity trains on safety grounds on Monday, stranding hundreds of thousands of commuters in an 11th-hour response to two weeks of limited work bans planned by the Rail Tram and Bus Union.