Video report by ITV News' Correspondent Romilly Weeks, words by ITV News Westminster Producer, Lucy McDaid
Nearly 200,000 hospital appointments and operations had to be re-scheduled during last week's four-day walkout by junior doctors in England.
Latest NHS figures reveal at the height of the strike period, 27,361 staff members were not in work due to the industrial action taking place over pay.
The prime minister warned on Monday that continuing strikes will make tackling the NHS waiting list "more challenging."
It currently stands at a record 7.22 million people, despite a reduction in the numbers waiting more than 18 months.
A total of 196,225 hospital appointments and procedures had to be rescheduled last week when junior doctors from the British Medical Association (BMA) walked out over four days, with one NHS chief warning the impact on patients will only "continue to worsen."
It comes as the UK's largest nursing union, the Royal College of Nursing (RCN), voted to reject the latest government pay offer and plan a further walkout at the end of the month.
Nurses' strikes will make tackling the NHS backlog 'more challenging', warns Rishi Sunak
NHS national medical director, Professor Sir Stephen Powis, responded to the latest data and said the impact on both staff and patients will "unfortunately continue to worsen".
"Today’s figures lay bare the colossal impact of industrial action on planned care in the NHS," said Professor Powis.
"Each of the 195,000 appointments postponed has an impact on the lives of individuals and their families and creates further pressure on services and on a tired workforce – and this is likely to be an underestimate of the impact as some areas provisionally avoided scheduling appointments for these strike days.
“Our staff now have an immense amount of work to catch up on hundreds of thousands of appointments, all while continuing to make progress on tackling the backlog of people who have been waiting the longest for treatment.
"We have now seen nearly half a million appointments rescheduled over the last five months, and with each strike, it becomes harder. While our staff are doing all they possibly can to manage the disruption, it is becoming increasingly difficult and the impact on patients and staff will unfortunately continue to worsen.”
The Chief Executive of NHS Providers, Julian Hartley, similarly warned the NHS will suffer if the strikes continue.
Mr Hartley said the "overall impact" of industrial action will be hard to judge immediately, but it will have a "significant impact" on the ability of the NHS to "eat into" the record backlog if it continues much longer.
'There's no doubt that if strikes continue indefinitely, that will have a significant impact' on the NHS' ability to tackle the waiting list, the NHS Providers chief executive warns
Meanwhile, while briefing journalists on Monday, the prime minister's official spokesperson ruled out any new pay offers in a bid to avert further strike action, maintaining that what's on the table is "fair and reasonable".
"The Royal College of Nursing was clear that talks will not be reopened if members reject the pay offer and we agree," the spokesperson said.
On Friday, members of the Unison union voted to accept the latest offer for paramedics and other health staff, which proposes a 5% pay rise for 2023/24 and a one-off cash payment of around £2,500 for last year.
But members of the RCN, regardless of what other unions vote, will return to the picket lines from April 30 until May 2. The next walkout will mark a dramatic escalation, with a clear warning from Mr Barclay that it will "put patients at risk".
The RCN's general secretary Pat Cullen disputes claims about patient safety, arguing to ITV News that "patients are at risk every single day".
'This is in the hands of the government', insists RCN general secretary Pat Cullen
Echoing Mr Barclay's sentiments, the prime minister described the RCN's rejection of the pay deal on Friday as "obviously disappointing".
His comments come after Ms Cullen confirmed plans to re-ballot RCN members, meaning industrial action could continue up until Christmas if the deadlock over pay isn't resolved.
Mr Sunak also said he remains "hopeful" that NHS waiting times can be driven down.
He said: "Last year we hit the first of those targets, which was to practically eliminate the number of people waiting two years for treatment, which is obviously unacceptable, so that was done and accomplished.
"In spring this year I said we would practically eliminate those waiting a year-and-a-half for their treatment and we were on track to do that - the industrial action obviously makes that more challenging but we are pushing hard to meet that target."
Mr Sunak added that he hopes the one-year waits will be eliminated by next spring with the overall waiting list also falling.
"I do remain hopeful," he insisted, but "of course industrial action makes these things more challenging," he added.
On the next planned strikes by RCN nurses, Mr Sunak added: "I think voting to strike with no derogations, given the closeness of the vote, is obviously disappointing and everyone will be concerned about the impact on patient care."
He added: "Our door's always open to have talks and there are other unions who are currently in the process of balloting their members, and, hopefully, they can see that the offer that we put forward is a reasonable one that recognises their hard work and the contribution they make, and also recognises that we have to do these things in a way that's affordable for taxpayers, but also gets inflation down."
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