Hospital consultants in England are striking for 48 hours from Thursday in a bitter row over pay, with patients being warned to expect “severe delays” and that routine care could come to a standstill.
The British Medical Association also announced plans for walkouts later in the year, from September 19 to 20 and October 2 to 4.
As thousands of the most senior hospital doctors will be away from work, National Health Service leaders are anticipating “major disruption” during the current walkout.
Emergency care will continue to be provided, with consultants delivering “Christmas Day cover” during the strikes.
Health experts warned that the “grim milestone” of one million postponed appointments is on the horizon.
The number of inpatient and outpatient hospital appointments cancelled in England since the current spell of industrial action began in the NHS in December 2022 now stands at 839,327.
If the community and mental health figures are included, the total rises to nearly 900,000 – although this will not reflect the overall number of actual cancellations because of some duplication of data.
Concerns have also been raised about the timing of the strike – just before the bank holiday weekend – which could put many services out of action for five days.
Many staff will be on annual leave and the warmer weather in recent days could lead to a rise in demand for care, NHS leaders said.
This could mean patients could face “severe delays”, experts said.
The government has insisted that talks on pay are over after it offered consultants a 6 per cent rise.
The BMA has condemned the increase as insulting, claiming that consultants have experienced a “35 per cent pay erosion” over the past 14 years.
“This latest action will again hit the NHS hard, with almost all routine care being affected," said NHS England’s national medical director for secondary care, Dr Vin Diwakar.
“It also comes at a time when many staff are taking annual leave, so teams are already stretched, and some parts of the country have seen warm weather this week, which usually leads to an additional rise in demand for services, so we would ask people to take the usual precautions.
“We are working closely with unions to ensure we prioritise urgent and emergency care for patients, as ever, but there is no doubt that it becomes harder each time to bring routine services back on track following strikes.
"And the cumulative effect after nearly nine months for patients, staff and the NHS as a whole is enormous.”
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People should continue to call 999 for life-threatening emergencies and NHS 111 for other health concerns, officials said. GPs and pharmacies are largely unaffected.
“A two-day strike by senior doctors just before a bank holiday weekend and when many staff are on well-deserved summer holidays is a massive headache for the NHS," said Sir Julian Hartley, chief executive of NHS Providers.
“Trust leaders have once again put plans in place for cover and to minimise disruption as far as possible. But that gets harder and more expensive with every strike.
“Official figures show more than 897,000 routine procedures and appointments have been delayed due to strikes across the NHS since December.
"The true figure, including appointments that weren’t booked in because of industrial action, is likely to be significantly higher. And strikes have cost the NHS an estimated £1 billion ($1.27 billion).
“The government and unions must find a solution urgently.”
Danny Mortimer, deputy chief executive of NHS Confederation, said: “With strike action backing on to a bank holiday weekend, this round will again have a significant impact on patients.
“Demand at A&E departments is usually higher on bank holiday weekends but this, combined with operating a Christmas Day level of service in the run-up, means that increased pressures will in many places mean patients will be faced with severe delays.
“All sides must do whatever it takes to avert the further walkout planned by consultants for September and prevent the NHS from reaching the grim milestone of one million cancelled operations.”
Dr Vishal Sharma, the BMA consultants committee chairman, said: “No consultant wants to be striking and we head out to picket lines today with heavy hearts.
“We would much rather be inside the hospital seeing our patients.
"But we cannot sit by and watch passively as we are persistently devalued, undermined and forced to watch colleagues leave, much to the detriment of the NHS and patients.
“By refusing to talk to us – and it’s now been 150 days since the Health Secretary met with us – it just shows that the government is not serious about the NHS, its workforce or patients.
“Our message to the Prime Minister is that we are serious about protecting the consultant workforce and thereby the NHS and patients.
“We are striking today, and will do so again in September and October, but the Prime Minister has the power to avert any further action at all, by getting around the table and presenting us with a credible offer.
“Consultants are clear that they’re prepared to take regular action and politicians must be left in no doubt that our dispute will not go away simply because they refuse to negotiate. We will not be ignored.”
Health and Social Care Secretary Steve Barclay, said: “I am concerned and disappointed that the BMA has gone ahead with this industrial action, which will continue to affect patients and hamper efforts to cut NHS waiting lists.
“I’m aware some consultants cut short their annual leave over the most recent periods of industrial action by the BMA junior doctors' committee and I am incredibly grateful to those staff who came forward to help protect patients and services.
“We have accepted the independent pay review body recommendations in full, giving consultants a 6 per cent pay rise, which means average NHS earnings for consultants of £134,000, on top of a pension where generous tax changes mean a consultant can retire at age 65 with a pension each year for life of £78,000 a year.
"This pay award is final and I urge the BMA to call an end to strikes.”
Wes Streeting, Labour’s shadow health secretary, said: “The Conservatives have given up any attempt to solve strikes in the NHS.
[Prime Minister] Rishi Sunak refuses to speak to doctors and instead shamelessly uses them as an excuse for his failure to cut waiting lists.
“Patients don’t want excuses, they want action. If the Conservatives have given up on governing, they should step aside and let Labour clean up their mess.
“There were no national NHS strikes when Labour was last in office. We need a government that will treat NHS staff with respect, open its door for talks and bring these strikes to an end.”
Consultants will take to picket lines from 7am on Thursday until 7am on Saturday.
It is the second round of strikes consultants have staged in the current dispute, with thousands of medics absent from work during the first walkout in July.
Junior doctors are continuing their dispute with the government and a third group of hospital doctors in England – specialist, associate specialist and specialty doctors – are planning for an indicative ballot on industrial action, “unless the government makes an offer to urgently improve their pay and working conditions”, the BMA has said.