The boss of the Rail, Maritime and Transport Union has been barred from talks aimed at resolving the dispute which has brought the Southern Rail network to a standstill.
The RMT has revealed that Mick Cash has been refused permission to take part in the talks, which come amid a fresh wave of strikes which have forced the cancellation of all Southern trains.
Southern Rail bosses are sitting down for talks at the conciliation service Acas with the RMT, which represents train guards, and Aslef, which represents the drivers.
Cash said: "Southern Rail were fully aware last night that I would be attending the talks this morning at Acas alongside our Aslef colleagues.
"This morning, on arrival for the talks, I was told that I would not allowed to take part by representatives from the company.
"RMT is furious at the complete contempt that has been shown to us by Southern Rail this morning which leaves us in a state of limbo when we should all be around the table thrashing out the issues that have led to the current action.
"Our members were expecting discussions to take place today and instead we have had the door slammed in our faces. That is no way to rebuild the confidence of the workforce in the Southern management and the talks process and it is no way to reach a solution which is what the public are crying out for.
"I will now be reporting back to RMT's executive on these developments.”
The dispute centres on the role of conductors on the Southern network. The unions claim drivers should not be obliged to operate train doors as their job is already complicated and demanding enough, and that a separate individual is required to operate the doors.
Southern claims it has put forward a perfectly reasonable compromise solution, but this stance is rejected by the unions.
Representatives of both Southern and the unions have spoken to talkRADIO in recent weeks. Julia Hartley-Brewer asked Southern director Alex Foulds why the current mess can't be sorted out during an at-times testy conversation, while the boss of Aslef, Tosh McDonald, appeared on our show yesterday to insist that his members' concerns were genuine and there is a real safety risk if drivers are forced to operate train doors.