Junior doctors in the National Health Service (NHS) of England have initiated a six-day strike, marking the longest union action in the NHS's 75-year history. 

Tens of thousands of patients are set to face canceled or postponed appointments, including those with critical conditions such as cancer and sight problems, according to the report. 

Health charities have expressed deep concern, warning that the disruption caused by the strike may leave patients anxious, upset, and at risk of their conditions deteriorating due to delayed medical assistance.

Additionally, the Patients Association emphasized potential compromises to patient safety, citing insufficient hospital staff to manage the impact of the prolonged strike.

The strike, which commenced at 7 am on Wednesday, comes after unsuccessful negotiations over junior doctors' pay between British ministers and the British Medical Association (BMA) before Christmas. The Patients Association has urged both parties to bring in mediators to resolve the prolonged dispute.

Strike poses challenge for NHS

The national medical director of the NHS, Prof Sir Stephen Powis, highlighted the cumulative effect of 13 months of strikes, involving doctors, nurses, and other staff, on the healthcare system. This week's strike marks the tenth by junior doctors since March.

The Royal National Institute of Blind People voiced particular concern about blind and partially sighted patients, who may not be aware of canceled appointments due to the mode of communication.

The timing of this strike poses a significant challenge for the NHS, already grappling with a surge in winter illnesses. 

The BMA junior doctors committee has been advocating for a 35% pay rise to address in real terms the decline in physicians' pay since 2008-09. Dr Robert Laurenson and Dr Vivek Trevedi, co-chairs of the committee, urged Health Secretary Victoria Atkins to deliver the promised improved pay offer.

Read more: Exodus of experience: Senior doctors leaving NHS for pastures new

Insufficient funds and promises

After the strike was announced in late December, UK Prime Minister Rishi Sunak said  "We would encourage junior doctors to consider carefully the extremely significant impact striking at such a challenging time will have both on the NHS and for individual patients and to return to talks".

Hospital administrations have criticized the move as being their "worst fears realized". 

Earlier in December, the British Medical Association (BMA) announced the decision for the strike after talks with the government fell through, stating that junior doctors have been offered a 3% raise on top of the 8.8% increase given earlier this year. 

However, the offer was rejected as a result of the cash due being split unevenly across different doctor grades and would "still amount to pay cuts for many doctors".

Junior doctors in Wales will also walk out for 72 hours from January 15 while those in Northern Ireland are being balloted for potential strike action but Scottish counterparts have already struck a deal with the government.

According to NHS England's national medical director, Stephen Powis, the strike will lead to a "huge disruption" and "put the NHS on the back foot".

The last time junior doctors in the UK walked out was back in August. 

The development comes as millions of patients in England are added to waiting lists to begin receiving medical care in hospitals as a result of a significant backlog caused by the pandemic and ongoing strikes by healthcare workers who are demanding more pay amid the UK's cost-of-living crisis.

Read more: Read: England's health service braces for 'catastrophic' doctors' strike