RMT members are to stage a fresh strike on 2 June in a long-running dispute over pay, jobs and working conditions.
The strike will see 20,000 train managers, caterers and station staff all walk off the job.
There will be three rail strikes within four days with Aslef train drivers walking out on 31 May and 3 June, the day of the FA Cup final.
The government said the RMT had gone “out of their way” to make life difficult for thousands.
The stoppages are also likely to cause disruption for many during the half term school break.
The RMT said no new proposals had been put forward by the train companies since the union’s last strike action on 13 May.
General secretary Mick Lynch said the government was not allowing the Rail Delivery Group (RDG) to make an improved offer in the national dispute.
Industry negotiators were “blindsided” when the RMT turned down their latest offer in April. There was a war of words over whether the RDG had gone back on its proposals – something it strongly denied.
On Thursday, the train companies’ group said it had continued to stand by its “fair” proposal, and said the RMT leadership had chosen to “to prolong this dispute without ever giving their members a chance to have a say on their own offer”.
Aslef’s walkouts are now more disruptive than the RMT’s, because settling the separate Network Rail dispute in March means signalling staff are no longer involved.
However, RMT members have backed strike action potentially into the Autumn.
The government and industry argue the railway is financially unsustainable, and working practices need to change to enable a pay rise.
Unions argue jobs and conditions are being attacked and the wage increases on the table are far below inflation.
“Ministers cannot just wish this dispute away,” the RMT’s Mick Lynch said.
On Thursday the government called again for the union to allow its members to have a vote on what it described as the “fair and reasonable offer” tabled by the RDG.
A spokesperson for the Department for Transport also said: “It’s extremely disappointing that for the second time in a month, RMT has decided to call strikes on the same weekend as Aslef, going out of their way to make travelling by train to the FA Cup final, Epsom Derby and a number of music concerts more difficult for thousands of people.”
The 14 train companies affected by the RMT’s ongoing strike action are: Chiltern Railways, Cross Country Trains, Greater Anglia, LNER, East Midlands Railway, c2c, Great Western Railway, Northern Trains, South Eastern, South Western Railway, Transpennine Express, Avanti West Coast, West Midlands Trains and GTR (including Gatwick Express)