NHS bosses are facing a backlash against plans to scrap a target to treat patients within four hours of arrival at A&E.

The body that represents A&E doctors said the move was an attempt to “bury problems” in the NHS. The proposal has sparked fears of a return to the days when some patients waited many hours in A&E to start treatment.

Dr Taj Hassan, president of the Royal College of Emergency Medicine (RCEM), said: “In our expert opinion scrapping the four-hour target will have a near-catastrophic impact on patient safety in many emergency departments that are already struggling to deliver safe patient care in a wider system that is failing badly.

“Let’s be very clear: this is far from being in the best interests of patients and will only serve to bury problems in a health service that will be severely tested by yet another optimistic reconfiguration.”

His colleague Derek Prentice, chair of the college’s lay group, went further, calling the plan an “attack on the patient interest” and accusing the NHS England chief executive, Simon Stevens, of being “hellbent on undermining the benefits that the four-hour A&E standard has delivered over many years”.

Prentice added: “I would have thought that no one wants to go back to the days of endless hours of waiting in A&E departments. The only ones who will benefit from this are ministers and NHS managers.”

The NHS constitution states that 95% of patients should be treated and then discharged, admitted or transferred within four hours. The NHS’s inability to meet the target in recent years has caused serious discomfort for ministers.

Stevens told MPs on Monday that the target will be “significantly altered”. Under the new plan, people with more serious conditions such as sepsis or heart trouble will be treated faster but those with minor ailments may have to wait longer.

Anna Crossley, the Royal College of Nursing professional lead for acute and emergency care, said: “It is imperative that hospitals have the staff and resources to give timely care within current guidelines. Tinkering with targets to make them easier is the wrong approach. Axing it or loosening it without evaluating alternatives puts patient safety at risk and sends a terrible signal that waiting times do not matter.”

Separately, NHS England is under pressure to explain which medical groups it has included in a review of its key clinical targets, which Theresa May ordered last year.

NHS England’s national medical director, Prof Stephen Powis, who is leading the review, said it was working with the Academy of Medical Royal Colleges and Healthwatch England to examine “what matters most to patients … and what they believe will help NHS staff provide the best quality care for patients”.

He said any changes would be trialled before being rolled out nationally.