Australia's busiest rail system is on the brink of meltdown, with officials predicting chaos as hundreds of cancellations continue for some time.
NSW's train drivers appear unlikely to accept a marginally increased pay offer and end their long-running battle with the state government, with no end in sight after three days of industrial action that could progressively cripple the network.
By 2pm on Wednesday, 400 train services had been cancelled with the figure tipped to reach 1000 by the end of the day, as 80 per cent of all services are affected.
Some trains stood still at platforms for more than 30 minutes as the action backed up the system, government officials said.
Sydney Trains chief executive Matt Longland forecast things could get worse, as work bans stopping critical maintenance work would progressively cripple the system.
Along with those bans, drivers have lowered their speed limits by 23km/h on some sections of track.
"The advice we've received, particularly from the Electrical Trade Union, is there will be no movement on their work plan (and) these sorts of delays that we've seen today will continue into the day tomorrow," Mr Longland said.
"The reality is, if this action continues in the coming days, we will see similar levels of impact, and potentially it may get worse."
Work bans, including cancellations, continue while the union considers the government's wage offer. (Mick Tsikas/AAP PHOTOS)
The government offered a 15 per cent pay bump across four years on Tuesday, way below the the four annual wage increases of eight per cent the workers have been asking for.
Transport Minister Jo Haylen apologised for the transport turmoil and said the government was contemplating legal avenues to stop the go-slow.
But she could not outline any imminent actions that might ease commuter pain.
"Passengers are unfortunately paying the price here for the union's actions … we want that resolved as soon as possible, and the way to do that is for the employees to accept the fair and reasonable offer that is on the table," she said.
Transport Minister Jo Haylen says the pay increase was the government's final offer. (Steven Markham/AAP PHOTOS)
But Rail, Tram and Bus Union state secretary Toby Warnes suggested the offer remained "significantly" below what members would accept.
He urged government officials to re-engage in negotiations rather than issue an ultimatum.
Ms Haylen said on Wednesday the proposed deal was a "final offer".
"Those figures have to increase significantly … it really comes down to sitting at the bargaining table with the government and going through the numbers," Mr Warnes told ABC TV.
Rail, Tram and Bus Union state secretary Toby Warnes says a wage offer was "a little light-on". (Dan Himbrechts/AAP PHOTOS)
The government had previously refused to budge from its initial, public sector-wide pay offer, but it said a merger between NSW's two rail bodies and "productivity gains" - which the union tipped to include 100 job cuts - allowed for the slight bump.
Mr Longland said he respected the rights of workers to take action but those not completing full tasks would be docked pay.
Sydney Trains has set a Thursday deadline for the union to provide an in-principle response to the offer.