A leading health union has accepted the government’s improved pay offer for NHS staff, in a move that could split unions over whether to keep on striking for more money. GMB members working in the NHS in England have voted by 56% to 44% to accept the deal that all 12 health unions hammered out last month with the health secretary, Steve Barclay. The GMB’s decision came hours after another union, Unite, rejected the deal and the NHS continued to gear up for a new nurses strike on Sunday. That means two of the main NHS-related unions have accepted the deal – Unison has already done so – as have unions representing midwives and physiotherapists. But two other unions – Unite and the Royal College of Nursing (RCN) – have rejected it, as have those representing podiatrists and radiographers. Those differences will be aired next Tuesday when the NHS staff council, which represents all 12 unions, meets to debate and vote on the improved offer for both last year and this. The staff council operates on an electoral college system in which unions’ voting strength is proportionate to the size of their membership. Union insiders say that system, allied to the unions’ decisions so far, mean it is likely the council will vote to accept the deal. Nevertheless, that could lead to a fracture in the coalition of NHS unions, with Unite continuing to strike for a better NHS deal and the RCN doing the same if it gets a renewed legal mandate from a ballot of its members. The GMB and Unite’s ballot results came amid rising concern in the NHS in England that this weekend’s strike by nurses could leave hospitals desperately short of staff and put patients at risk. NHS Providers, which represents health service trusts, said some were “struggling to find enough staff”. Great Ormond Street children’s hospital in London said it had “serious concerns” over how it would be able to look after its patients, many of whom are critically ill, over the weekend. The hospital is so concerned that on Friday it declared a “business continuity incident” to protect patient safety. Tens of thousands of nurses belonging to the RCN are expected to stage a 28-hour stoppage from 8pm on Sunday until midnight the next day with – for the first time since they began striking in December – no exemptions for life-or-death areas of care such as A&E and intensive care. “We respect the right of our staff to take part in lawful industrial action. But after exhausting all options, at the moment we have serious concerns over how we will safely staff our hospital during the strike”, said Mat Shaw, Great Ormond Street’s chief executive. They are unhappy with the improved pay deal. It would give NHS staff in England, apart from doctors and dentists, a one-off non-consolidated payment of between £1,250 and £2,000 for 2022-23, on top of the £1,400 rise in basic pay they have already received – the sum that prompted nurses, ambulance staff and other health workers to stage a series of strikes starting in mid-December. It also includes a 5% rise in basic pay for 2023-24. The RCN’s strike was due to last until 8pm on 2 May. The union suffered a humiliation on Thursday, however, when the high court in London declared that its planned strike on that day was unlawful because its legal mandate, arising from a ballot last autumn, expired on 1 May.