Sydney train commuters could face further disruption to services after rail workers voted to take industrial action as they continue fighting for a six per cent a year pay rise and improved conditions.
The result of the ballot - announced on Friday afternoon by the Rail, Train and Bus Union - comes at the end of a week in which the city's train network went into meltdown with mass cancellations and delays.
The government blamed the chaos on drivers calling in sick and storm damage but it was later revealed management had also approved "excess" annual leave.
"An incredible result, well done Sydney and NSW Trains! By standing together and returning a YES vote we have shown management that we are strong and united in our demand for a good agreement," the union said on its Facebook page on Friday.
A strike is yet to be confirmed with union delegates and members meeting in coming days to discuss precisely what action they'll take.
Options being considered include partial work bans, stoppages or extended strike action.
RTBU NSW secretary Alex Claassens insists industrial action is a "last resort".
"Management are in a position to avoid that situation and we're still very hopeful they'll come to the table and negotiate a fair and reasonable offer before we get to the point of action," he said in a statement.
"All workers are asking for is a commitment to protecting their basic workplace conditions and a fair wage increase but management is currently refusing to provide that."
The union claims this week's mayhem was partly due to a new more-intensive timetable introduced late last year which leaves little room to recover from incidents on the network.
Rail bosses met with union heavyweights on Thursday to discuss the problems ahead of a "pressure day" expected on Monday when the new Hornsby junction begins operating and excess leave approvals could again frustrate commuters.
Transport Minister Andrew Constance has demanded a review of the timetable within a fortnight.
On Friday evening he urged union bosses to put the needs of commuters "before unnecessary strike action" and reiterated that any pay rise needed to be within the 2.5 per cent cap for public servants.
"The government will agree to a pay rise for train drivers in accordance with the wages policy ... that applies to teachers, nurses, police and all public sector employees," he said in a statement, adding that Sydney Trains had 9550 award staff of which only 3007 voted for strike action.