Industrial action may be playing havoc on the Greater Sydney rail network, but XPT regional services from Dubbo and connecting coaches have so far dodged the bullet.

 Transport for NSW (TfNSW) said that 576 drivers and guards did not turn up to work as of 2pm today after the Rail, Tram and Bus Union's (RTBU) planned action went ahead this morning.

The union said late on Thursday night that negotiations for a new pay deal with the NSW government had collapsed.

There are currently no direct impacts on the Dubbo trains, however, passengers should be aware that this could change and that connecting services in other areas may not be available.

"Passengers are urged to delay non-essential travel as there are lengthy delays, service cancellations and very large service gaps are expected on the rail network today due to a high level of staff absences due to industrial action," a TfNSW spokesperson said.

"Services will be affected on all lines but will be particularly impacted on the South Coast Line where there are no train services running."

To 1:30pm today (Friday 14 February), more than 800 services were cancelled and 396 services delayed.

A government spokesperson said they were blindsided by a "last hour" demand by the union for a $4500 bonus payment for every rail worker.

The union's secretary Toby Warnes said the bonus was an existing entitlement under the last enterprise agreement.

Transport Minister John Graham said the government was seeking a hearing with the Fair Work Commission today to stop the industrial action.