Obese people and smokers face being increasingly denied NHS surgery as hospitals impose cost-cutting measures, leading medics have said.
Their warning comes as a North Yorkshire authority said that patients who exceed a body-mass index (BMI) of 30 will be denied non-life threatening surgery for up to a year.
The restriction by the Vale of York clinical commissioning group (CCG), which will also apply to smokers, was described as the "most severe" policy the modern NHS has seen by the Royal College of Surgeons (RCS).
Reports of the rationing also sparked criticism from former health minister Norman Lamb as "outrageous".
Obese patients may secure a referral in less than a year if they shed 10% of their weight, the Vale of York CCG said.
Similarly, if smokers refuse to quit they face having procedures delayed for up to six months, which can be accelerated if they quit their habit for eight weeks.
NHS Providers, which represents NHS leaders, said similar decisions like this were likely to follow in future.
A spokesman said a number of considerations are taken by health services outside of costs when considering the decision to operate, but added: "However, given that we are in the middle of the longest and deepest financial squeeze in the NHS's history, we are likely to see more decisions like this in future.
"What is important is that this is managed on an NHS-wide basis.
"There is now a clear and widening gap between what the NHS is required to deliver and the funding available, and this will only get worse as overall funding increases drop from next year."
In April, the RCS found almost a third of CCGs have one or more mandatory policies on BMI level, stopping overweight or obese patients being referred for routine surgery.
Cancer patients are not included under the scope of such policies.
The RCS has previously said that overweight people and smokers are "soft targets" for NHS savings.
Body Mass Index (BMI), which relates a person's weight and height, is used by experts to define overweight and obese limits.
People described as overweight have a BMI of 25 to 29.9. Those with a BMI of 30 to 35 and above are said to be moderately obese, while someone whose BMI is higher than 40 is classified as severely obese.
The president of the RCS, Clare Marx said: "The policies being introduced by Vale of York CCG are some of the most severe the modern NHS has ever seen.
"Smokers and overweight patients should unquestionably be helped to stop smoking or lose weight prior to surgery for their overall health.
"We would support any attempts by Vale of York to expand its weight loss and smoking cessation programmes, but introducing blanket bans that delay patients' access to what can be life-changing surgery for up to a year is wrong."
Mr Lamb, a Liberal Democrat who served as minister for state care and support in the Department of Health between 2012 and 2015, said: "This is just the latest in a growing list of local decisions to ration care.
"Any rationing not based on clinical need is outrageous. But it is caused by the Conservative government persisting with plans to reduce the share of our national income spent on the NHS."