RMT members working for the 14 train companies in the national rail dispute will walkout on Friday June 2.
The union found the RDG’s previous offer and associated conditions unacceptable and despite contact between the parties since the struck on May 13, no new proposals have been formulated for the RMT to consider.
The strike on June 2 will see 20,000 railway workers in catering, train managers and station staff all take action, affecting train services throughout the country.
RMT general secretary Mick Lynch said: "The government is once again not allowing the Rail Delivery Group to make an improved offer that we can consider.
"Therefore, we have to pursue our industrial campaign to win a negotiated settlement on jobs, pay and conditions. Ministers cannot just wish this dispute away."
The 14 train operators are as follows:
Cross Country Trains
East Midlands Railway,
Great Western Railway,
South Western Railway
Avanti West Coast,
West Midlands Trains
GTR (including Gatwick Express)
A spokesperson said: "They underestimate the strength of feeling our members who have just given us a new 6-month strike mandate, continue to support the campaign and the action and are determined to see this through until we get an acceptable resolution.
"The government now needs to unlock the RDG and allow them to make an offer that can be put to a referendum of our members."