Network Rail said there was “no real hope” of avoiding the biggest railway strike in 30 years next week, as it told passengers to plan ahead and only travel if necessary. The walkouts are on 21, 23 and 25 June and a special timetable will be in operation from 20 to 26 June. The full timetable will be published on Friday but several operators including Southern, Northern and Transport for Wales have already told passengers not to attempt to travel on strike days. Network Rail confirmed that large parts of Great Britain would have no passenger services at all on strike days, including locations such as Penzance in Cornwall, Bournemouth in Dorset, all of Wales west or north of Cardiff, and no passenger trains running north from Glasgow or Edinburgh. With backup staff for signalling, about 20% of trains will run on mainlines and urban areas on the strike days, while services will start later in the morning, with about 60% of the schedule on the subsequent days. Network Rail’s chief executive, Andrew Haines, described the strike by 40,000 RMT workers as a “high-stakes gamble” by unions, and said it would cost the industry £150m and make a pay increase harder. Haines said proposals to modernise to increase safety and productivity were meeting “intransigence … even when terms and conditions are patently anachronistic”. He said talks would continue but added: “We haven’t yet seen movement that gives us real hope.” The RMT called for direct talks with the government, saying it was “clear that the Treasury is calling the shots”. Mick Lynch, the RMT’s general secretary, wrote to the transport secretary, Grant Shapps, to seek an urgent meeting, saying: “In effect, in recent weeks the union has been negotiating with the government but the government have not been in the room.’’ The last meeting between unions and the government was with the rail minister Wendy Morton in March. Labour accused the government of a “dereliction of duty” for failing to hold talks to resolve the strike. The shadow transport secretary, Louise Haigh, said it was “frankly extraordinary” and wrote to Shapps calling on him to convene urgent talks. In a Commons debate later on Wednesday, Shapps said it was a “red herring”, adding: “These negotiations are a matter between the employer and the union.” The transport secretary said the strikes were “entirely pointless, counterproductive” and the industry needed to be modernised. He told MPs: “Our railway needs a new direction. It has lost 20% of its passengers and 20% of its revenue too. “We protected the railway with £16bn during the pandemic … not a single railway worker lost their jobs or were furloughed. This level of subsidy cannot continue forever.” The former Labour leader Jeremy Corbyn responded: “The rail companies were preserved and supported and did very well, as did many others in the private sector. Why is he now punishing those people that kept the railway system working, that do all the difficult jobs on the railway, with job losses, inadequate pay and a loss of morale?” Grant Shapps said he paid tribute to those people – but a train driver had a median salary of £59,000, and the median within the rail sector was £44,000. He added that rail workers had seen wages rise by 39% over the last 10 years compared with 7% for police. In response, Haigh said that no one wanted strikes, but they were not inevitable. She said: “The bad news is that it require ministers to step up, to show leadership, and get employers and unions round the table.” The number of passenger services on the strike days is expected to be limited to about 4,500 compared with 20,000 normally The last services between London and Scotland will leave by 2pm, while most intercity trains in England will have their final departure mid-afternoon. Steve Montgomery, who chairs the Rail Delivery Group, representing train operators, said: “Working with Network Rail, our plan is to keep as many services running as possible but significant disruption will be inevitable and some parts of the network will not have a service, so passengers should plan their journeys carefully and check their train times.”