Workers at three rail companies are to launch a fresh wave of strikes in long-running disputes over staffing and driver-only trains.
Members of the Rail, Maritime and Transport (RMT) union at Southern Railway and Arriva Rail North will walk out on Friday September 1 and Monday September 4.
Strikes will be held at Merseyrail on September 1, 3 and 4.
The union accused the companies and the Government of pressing ahead with controversial plans to extend driver-only operation.
RMT general secretary Mick Cash said: "RMT is bitterly disappointed that Southern Rail have rejected our call for round-table discussions involving all parties with an interest in resolving this dispute.
"The failure to get those talks moving following our face-to-face meeting with Transport Secretary Chris Grayling has left us no option but to call further action.
"RMT pays tribute to our Southern Rail guards and drivers who have stood firm for well over a year in the fight for rail safety despite outrageous abuse and intimidation from the company. They are a credit to their communities and to the whole trade union movement.
"RMT has a clear plan for resolving this dispute but that requires round-table talks now to push forwards."
Mr Cash had a meeting with Arriva Rail North on Friday but accused the company of "intransigence", adding: "The responsibility for the inevitable disruption lies wholly with the company.
"We are angry and frustrated that Arriva continue to fail to face up to the facts and also continue to ignore a perfectly reasonable union proposal to invite the DfT (Department for Transport) to join us in round-table talks aimed at finding a solution.
"The public, who support RMT's campaign for a guarantee of a guard on their trains, will be appalled that Arriva Rail North have failed yet again to offer any kind of progress whatsoever in the talks and have instead opted to try and bulldoze through their plans regardless."
Mr Cash added: "It is disgraceful that Merseyrail continue to refuse all reasonable attempts by the union to settle this dispute.
"Merseyrail have repeatedly kicked all conciliatory approaches by RMT negotiators back in our faces and made it crystal clear that all that they are interested in is the union signing a surrender document which gives them a free hand to rip apart the safety culture on the railway."
Alan Chaplin, Northern's managing director, said: "Following our meeting with RMT's general secretary, there is no doubt that the trade union calling two days of strikes timed to coincide with people across the North returning to school, college and work after the holidays, will damage the region's economy, significantly disrupt our customers' lives, and impact local businesses.
"Northern is prepared to guarantee jobs and current pay for all our conductors for the next eight years, until the end of our franchise. Our offers to discuss every detail on the future responsibilities and training for on-board colleagues have been rejected by RMT.
"Northern is modernising with new and updated trains, faster and more frequent services, and better stations from now until 2020. We want to make changes to the on-board colleague role to make it fit for the future, better supporting customers on trains and at stations."
Jan Chaudhry-van der Velde, Merseyrail's managing director, said: "The RMT say this dispute is about safety but a recent industry report states that there is no additional risk for passengers boarding and alighting driver-only trains."
A spokesman for Southern Railway said: "We are disappointed by this unnecessary action and the RMT's refusal to engage with us in modernising the railway.
"We deeply regret any inconvenience this action will cause our passengers and we will make every attempt to minimise disruption.
"Modernisation is urgently required to future-proof and increase capacity on the busiest parts of the UK railway.
"This modernisation needs three things: investment in better infrastructure, new trains, and changes in working practices.
"The first two elements are being rolled out but the trade unions need to play their part if passengers are to benefit from service improvements."