Deadlock over NHS pay is putting patients in danger and risks hardening the position of unions, 10 chief nurses have warned on the eve of the biggest strikes in the health service’s history. Unions have warned that the government is making no moves towards resolving the strikes, with one general secretary accusing the government of lying about the state of negotiations. In a joint statement shared with the Guardian, chief nurses from 10 leading hospitals known as the Shelford group highlighted their concern that patients’ health could suffer as a direct result of the increasing disruption the stoppages are causing. Tens of thousands of nurses and ambulance workers in England will stage what will be the biggest strike in the NHS’s 75-year history on Monday. In a plea to the government and health unions, but especially ministers, the 10 Shelford group chief nurses stress that they want both sides to end their standoff as a matter of urgency “because of the impact on the patients and communities we serve. “Industrial action means appointments cancelled, diagnostics delayed [and] operations postponed. The longer industrial action lasts, the greater the potential for positions to harden, waits for patients to grow, and risks of harm to accumulate.” This week will see just one day – Wednesday – when there are no NHS strikes. Nurses will strike again on Tuesday, physiotherapists will stage their second walkout on Thursday and ambulance personnel will stage a further stoppage on Friday. The chief nurses blame nurses’ salaries – which have been eroded by years of below-inflation pay rises – for the NHS in England’s shortage of 47,000 nurses and the anger among nurses behind the ongoing action, which has become a stalemate between unions and the health secretary Steve Barclay. “Pay and reward is central to the dispute,” they say. A government spokesperson said Barclay was ready to resume talks. “The Health and Social Care Secretary has held constructive talks with unions on pay and affordability, and he continues to urge them to call off the strikes and come back around the table.” But Sharon Graham, the general secretary of Unite, said there were no discussions taking place. “In 30 years of negotiating, I’ve never seen such an abdication of responsibility in my entire life,” she said. “Rishi Sunak is the CEO of UK plc. We are trying to sit down with him and do a negotiation. It’s very difficult to do a negotiation to solve a dispute like this if they won’t even come to the table.” She said she could say “categorically that there have been no conversations on pay whatsoever with Rishi Sunak or Steven Barclay about this dispute in any way, shape, or form. They dance round their handbag, dance round the edges, but they will not talk about pay. And to me, that is an abdication of responsibility.” Sources at Unison have also expressed bewilderment at government claims that there were talks ongoing – saying the government had briefed in early January that they were ready to discuss a potential one-off payment or backdated pay rises but that there was no offer available to discuss. Patricia Marquis, director of the Royal College of Nurses in England, said the Shelford letter was a “welcome intervention and ministers must heed the warnings”. She added: “England is now being left behind and Rishi Sunak is punishing nurses here by refusing to negotiate and pay people fairly. In Scotland and Wales nurses are being offered more and strikes are currently cancelled. England’s nurses cannot be left the lowest paid in the UK. The prime minister must act and stop these strikes.” The strikes by nurses, paramedics and other ambulance staff and paramedics that began on 15 December have already forced the NHS to cancel 88,043 operations and outpatient appointments in hospitals and community clinics. The mass walkout is expected to trigger the biggest suspension of NHS care yet seen, easily exceeding the 15,779 cancellations that occurred on 15 December. The statement was signed by the chief nurses at England’s top 10 teaching and research hospital trusts, including University College London, Imperial College London and Guy’s and St Thomas’s trusts, all in the capital, and the trusts that run Addenbrooke’s in Cambridge, the Manchester Royal Infirmary and John Radcliffe hospital in Oxford as well as the acute hospital trusts in Birmingham, Sheffield and Newcastle. Their intervention comes a day after the NHS Confederation warned that patients could be putting their physical or mental health at risk if they shy away from seeking medical help on strike days, perhaps because they do not want to appear a “burden” on overstretched services. Unions have angrily rejected claims from the government that they are unable to adequately prepare for ambulance strikes which are therefore putting lives at risk. Grant Shapps, the business secretary, claimed on Sophy Ridge on Sunday on Sky News that while the Royal College of Nursing had shown responsibility in the strikes so far, unions representing paramedics, call handlers and other ambulance staff had not, endangering patient safety. Asked if walkouts will put lives at risk, Shapps replied: “I am concerned that it does, if you have a situation which has been happening so far where you don’t have cooperation between the back-up services – typically the Army – and the people who are striking. “We have seen the situation where the Royal College of Nursing very responsibly before the strikes told the NHS ‘This is where we are going to be striking’ and they are able to put the emergency cover in place. “Unfortunately we have been seeing a situation with the ambulance unions where they refuse to provide that information. That leaves the Army, who are driving the back-ups here, in a very difficult position – a postcode lottery when it comes to having a heart attack or a stroke when there is a strike on.” NHS bosses have said that Unison, Unite and the GMB unions have agreed to respond to category one 999 calls on strike days – the most urgent, involving life-threatening situations – and have also abandoned picket lines to answer category two calls too.