Sweeping rail strikes next week will “go ahead as scheduled”, union chiefs have declared after being told there will be no new offer over pay.
Train firms made clear they will not propose a new deal, said the RMT - which has rejected a rise of 4% this year and next year.
That means a walkout at 14 train companies on December 13, 14, 16 and 17 appears unavoidable.
Network Rail workers - who are voting on a separate offer - are set to walk out on the same dates, and from 6pm on Christmas Eve to 6am on December 27.
Union sources said “we remain open for talks” but accused the government of sabotaging the talks with a last-minute intervention.
The RMT accused Tory ministers of ensuring “driver-only operation” on the railways was demanded as a “pre-condition” for a 4% pay rise on Sunday night.
The union said: “It is now absolutely clear that the RDG’s attempts to resolve the dispute by making a revised and improved offer have been blocked by the Government.”
It added: “RMT has just heard from the Rail Delivery Group and there will be no revised offer from them on the Train Operating Companies-side of the dispute.
“They have been instructed by the Government instead to take on the strike action set out, rather than trying to resolve the dispute through negotiations.
“The planned Industrial action for RMT Train Operating Company members goes ahead as scheduled as there is no resolution to the dispute.
“In fact a resolution to the dispute is now further away due to the Government’s late intervention in the negotiating process.”
Passengers are now being warned to plan journeys in advance and only travel by train if absolutely necessary, with TSSA and Unite also staging strikes.
Steve Montgomery, chair of the Rail Delivery Group, said the “deadline has passed where disruption could be avoided even if strikes were called off”.
He said train firms remained open to talks but accused the RMT of refusing to put the offer to its members.
Andrew Haines, Network Rail chief executive, said: “The RMT has deliberately chosen to try and ruin Christmas for millions of passengers and businesses.
“They’re also intent on inflicting a monumental act of harm on an industry still desperate to recover from post Covid challenges by sabotaging a vital £100m programme of rail upgrades planned for Christmas Day and Boxing Day.”
The Tory Transport Secretary refused to say whether the issue of driver-only operation had been inserted into negotiations at the eleventh-hour.
Mark Harper insisted: "No-one is trying to stop a deal - quite the reverse.
"We're trying to reach a deal here, it's the RMT that has rejected, and I think it's regrettable. I'm very clear I want to see a deal reached."
