Hundreds of thousands of Southern rail passengers are facing more travel chaos after talks between bosses and drivers' union Aslef ended with no deal on Tuesday evening (3 January).
The parties held negotiations at mediation service Acas in a bid to avert a week-long walkout from Southern drivers from 9 January.
"No agreement was reached," an Acas spokesperson said. "The parties have indicated that they remain available for further talks."
The dispute is over the future role of rail guards on the network, with Southern planning to allow drivers to close train door in conjunction with CCTV cameras.
Aslef and sister transport union RMT, which represents conductors on the franchise, have raised safety concerns about the modernisation proposals.
But Southern, operated by Govia Thameslink Railway, plans to press on with the new system.
"We very much hope Aslef will call off this strike but if they don't, we're working hard to see what we can do to help passengers," a Southern spokesperson told IBTimes UK. "We will be communicating those plans as soon as they are finalised."
The industrial dispute has also seen some major political interventions, with Prime Minister Theresa May describing an Aslef strike in December as "appalling".
Labour's Shadow Transport Secretary Andy McDonald has called for a pause in Southern's plans in bid to help resolve the dispute
"I'm constantly trying to move things along in my discussions with the parties that will engage," he told IBTimes UK.
"What I'm trying to secure is a pause – a moratorium, a breathing space – to allow people to step back and just acknowledge that this is a genuine safety crucial issue that needs to be addressed."
Londoners are also facing disruption on the Underground network, with station staff planning to strike for 24-hours from 18:00 GMT on 8 January.
Underground bosses and transport unions – the TSSA and RMT – plan to hold talks at Acas on 4 January.