Nearly 16,000 appointments, procedures and surgeries were rescheduled in England – 54,000 less than the Government suggested – when nurses staged their biggest ever strike in the history of the NHS.

The figures were published after Health minister Maria Caulfield said around 70,000 appointments would be lost due to the 12-hour industrial action.

But, according to provisional NHS data reported by trusts where the Royal College of Nursing (RCN) strike took place on Thursday, 2,452 inpatient and day case elective procedures and 13,327 outpatient appointments were rescheduled, coming to 15,779 in total.

Across England, 9,999 staff were absent from work due to the strike, according to figures on the NHS England website.

The highest numbers were seen in the South West where striking staff came to 2,372, with 2,023 in the Midlands and the next highest, 1,714 in the North East and Yorkshire.

Rishi Sunak is refusing to bow to pressure from health leaders and some senior Conservatives to negotiate pay with nurses to prevent further action.

The Prime Minister insisted on Friday that the offer given to nurses is “appropriate and fair” as they warned strikes will escalate without a better pay deal.

Four Conservative former ministers have urged Mr Sunak to back down, amid suggestions that asking the NHS pay review body to rethink their recommended deal could be a way out.

Nurses in England, Wales and Northern Ireland will walk out again on Tuesday without a breakthrough.

The strike involved around a quarter of hospitals and community teams in England, all trusts in Northern Ireland and all but one health board in Wales.

Despite the postponed appointments, polling showed that the majority of the public were in favour of strike action by nurses.

Mr Sunak and Health Secretary Steve Barclay were sticking by the pay deal recommended by the NHS pay review body in July and refusing to negotiate on salaries.

Speaking to the BBC during a visit to Belfast, the Prime Minister said: “The Health Secretary has always been clear, the door is always open, that’s always been the case.

“But we want to be fair, reasonable and constructive, that’s why we accepted the recommendations of an independent pay body about what fair pay would be.”

A health source was adamant that the pay review body would not be reconsulted, saying “if we unpick that settlement we will have to find billions more”.

“No, we are not going to do that,” they added.

Conservative chair of the Commons Health Committee Steve Brine has argued that the move would be an “elegant” and “sensible” way to avert further strikes.

Former Conservative Party chair Sir Jake Berry called for the Government to negotiate on pay, telling Times Radio: “Machismo and sort of chest beating and ‘we’ll take the unions on’ doesn’t work. You only get these things sorted out by talking.”

Dr Dan Poulter, a former health minister, argued ministers should up their offer because “inflation has significantly eroded real-terms pay” since the proposals.

Former justice secretary Robert Buckland told the PoliticsHome website “there must be a middle way” between the Government’s offer and the union’s demands.

Nurses were recommended a £1,400 raise, which is estimated to be an average of a 4.3% raise for qualified staff.

The RCN has been demanding a pay rise of around 19% but has indicated it is willing to accept a lower offer if ministers agree to negotiate.

It requested a rise at 5% above the RPI measure of inflation, which was running at 7.5% when they submitted their request to the pay review board in March.

But inflation has since soared, with RPI standing at 14.2% in September amid the Russian invasion of Ukraine.

RCN leader Pat Cullen has warned that action by nurses would escalate unless ministers back down on their refusal to negotiate on pay.

On Thursday, the NHS was running a bank holiday-style service in many areas, though the RCN was staffing chemotherapy, emergency cancer services, dialysis, critical care units, neonatal and paediatric intensive care, alongside several other services.