Train workers are set to stage three 24-hour strikes in a row over jobs, working conditions and safety.
Members of the Rail, Maritime and Transport (RMT) union on Virgin Trains East Coast will stage three separate one day-strikes in August, including on a bank holiday.
It is the latest outbreak of industrial action on the railways after RMT members on Eurostar launched a four-day walkout on Friday following strikes earlier in the week at Southern Railway.
The RMT said almost 200 jobs are threatened at Virgin Trains East Coast.
A statement said: "The ongoing dispute came to a head as the company chose to ignore the agreed negotiating machinery and subjected staff to a barrage of direct propaganda justifying their attempts to bulldoze through a package of cash-led measures that would decimate jobs, working conditions and threaten the safety regime that currently ensures a guard on every train."
RMT members will walk out from 3am on August 19, 26 and 29, and will ban overtime for 48 hours from August 27.
Virgin Trains East Coast operates services out of King's Cross and Edinburgh.
The union's general secretary, Mick Cash, said: "RMT will not sit back while nearly 200 members' jobs are under threat and while conditions and safety are put at risk by a franchise which is clearly in financial trouble.
"We will also not tolerate the cavalier attitude to safety that is now on show as the company mobilises its scab army of managers.
"Our members are being subject to outrageous intimidation and bullying as their trains are commandeered as part of the scabbing process.”
The union has also been locked in a bitter battle with Southern Rail over working conditions.
The RMT said the dispute involves around 1,800 of its members, including guards, station staff and some drivers. Depot maintenance workers will not be taking strike action.
