Sydney train drivers walked off the job on Monday, protesting in solidarity over contract deals.
Workers will take industrial action to try to highlight issues with the overtime ban and contractor policies.
The strike is expected to cause massive chaos and delays in the public transport sector as no services will operate between glenfield and sydney.
Buses will replace trains to start the working week as commuters in Sydney are affected.
New South Wales Minister for Transport David Elliot says it’s a big headache, adding that he will meet with the union to work out the bargaining deal.
“I think it’s unnecessary industrial action” Elliott told 2GB radio on Monday.
“No one is denying at the moment that many workers deserve a raise, but what workers deserve and what taxpayers can afford are two different things.”
It comes after the deadlock in negotiations on a new company agreement.
The industrial action could continue in various ways for almost three weeks.
Mr Elliott said commuters should check the NSW Rail site to plan ahead for delays on each line and check services.
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