Talks to avert a second national rail strike collapsed in rancour as the two sides traded insults in a bitter war of words as millions of passengers faced another day of disruption. In increasingly fraught negotiations, the head of the RMT hit out at the transport secretary, Grant Shapps, for “wrecking negotiations” in the dispute over pay, working conditions and proposed “modernisation” plans to cut costs after the pandemic. Shapps said the RMT claim was “a total lie”, while Network Rail claimed the union had walked away from talks. The rail industry asked passengers to travel only if necessary on Thursday, when fewer than one in five trains in Great Britain are expected to run as 40,000 RMT members working for Network Rail and 13 train operating companies go on strike. Services will be sporadic and limited to mainlines and urban areas between the hours of 7.30am and 6.30pm. Drivers from the Aslef union will also join strike action on Thursday on the Greater Anglia network. The RMT general secretary, Mick Lynch, blamed the transport secretary for the failure of talks: “Grant Shapps has wrecked these negotiations by not allowing Network Rail to withdraw their letter threatening redundancy for 2,900 of our members. “Until the government unshackle Network Rail and the train operating companies, it is not going to be possible for a negotiated settlement to be agreed. “We will continue with our industrial campaign until we get a negotiated settlement that delivers job security and a pay rise for our members that deals with the escalating cost of living crisis.” Shapps responded: “This is a total lie from the RMT and its general secretary. I have had absolutely nothing to do with either the issuing of a letter from Network Rail, the employer, to the RMT – or any request to withdraw it.” In a letter to the RMT leadership on Monday, Network Rail gave notice that it would start a formal process enabling 1,800 redundancies from 1 July, incorporating compulsory redundancies if necessary. It said it could not delay any longer plans to reform its maintenance regimes. Shapps added: “The RMT continues to deflect from the fact that the only people responsible for the massive public disruption this week is them. I want to urge Mick Lynch and his members to stop wasting time making false claims in the media and instead return to the negotiating table so an agreement can be reached.” A Network Rail spokesperson said: “We are disappointed that the RMT have again chosen to walk away from negotiations without agreeing a deal. We remain available for talks – day or night – and will do everything we can to avoid further disruption for our passengers.” A Rail Delivery Group spokesperson, representing train operators, said: “We call on the RMT leadership to continue to talk so that we can secure a thriving long-term future for the railway and its workforce.” The union has rejected offers of pay increases worth up to 3% from Network Rail and train operators, and has indicated it wants a cost-of-living settlement more closely linked to the RPI measure of inflation, which hit 11.7% in May. Rail staff at Merseyrail in the TSSA union voted to accept a 7.1% pay increase on Wednesday, and is believed the RMT is seeking a similar offer nationwide. Although the government has refused to get involved in negotiations, saying it was a matter for employers, the industry is currently bankrolled by the Treasury. Downing Street said on Wednesday it would be “reckless” to raise public sector pay in line with inflation. The prime minister’s spokesperson said: “It’s important to stress that does not mean we do not want to reward public sector workers with a pay rise, we do, it’s just we must make sure that we don’t do anything that has a knock-on impact which feeds into this global inflationary spiral that there is the potential to see.” The first day of strike action on Tuesday, which also coincided with a London Underground strike by another 10,000 RMT employees, saw relatively few passengers attempt to travel on the services that remained running, but crowded buses and jammed roads around the capital. Elsewhere, congestion appeared only slightly worse, with many people now able to work from home. Services were also disrupted on Wednesday morning, between the first two of the three planned strike days this week, with a later start in many areas and about 60% of the normal schedule planned to run across the day. However, Great Western Railway said it had been able to operate more “Glastonbury specials” to accommodate people travelling to the festival than it did in 2019, with nine departures from London Paddington to Castle Cary on Wednesday and five more planned during tomorrow’s strike. Meanwhile, bus workers at Stagecoach in Merseyside have voted to go on strike from the end of next week. The walkouts would join ongoing strikes in Yorkshire by drivers and depot workers for Arriva, which have stopped many services across the county for more than two weeks. More Arriva staff across north-west England are being balloted for strike action over pay.