A doctors' leader has accused Health Secretary Jeremy Hunt of calling the professionalism of hospital consultants into question after he told them to "get real" about the need for seven-day working.
British Medical Association chairman Mark Porter spoke out after a survey found nearly nine out of 10 doctors reported being on call at weekends and overnight.
Mr Hunt has given the BMA until September to negotiate changes to working contracts for hospital consultants and junior doctors to ensure "proper" seven-day services, warning that he is ready to impose a new contract if they cannot agree. He said around 6,000 people died every year due to a lack of senior staff at weekends.
His ultimatum sparked a protest petition as well as a Twitter campaign of medics who took photos of themselves in work over the weekend with the hashtag ImInWorkJeremy.
A BMA survey of nearly 900 consultants has found that 88% are on "non-resident on-call rota", meaning they can be called in to attend hospital in the evenings or weekends, said Dr Porter.
More than two-thirds said they were on call on Saturday or Sunday in the past week, working an average of six hours and half said they had their sleep disturbed on a weekend evening. A third had to go into the hospital to work during the night over the weekend, and only 30% of these were given rest time before starting their ordinary working week.
Dr Porter told The Independent: "The myths peddled by the Health Secretary on consultant working patterns are just that.
"Almost all consultants work evenings and weekends, and in areas like emergency medicine they have been the driving force behind delivering 24/7 working patterns, "Doctors are furious with Jeremy Hunt for calling into question their professionalism and dedication to their patients."
A Department of Health spokesman told the paper: "The BMA can't have it both ways: if most consultants do work weekends why are they objecting to removing the right to opt out of weekend work?
"If we are to reduce avoidable deaths, it isn't just the Health Secretary who is insisting on change: hospital leaders, senior clinicians, patient groups and the independent NHS pay review bodies all say the opt-out should be removed.
"The BMA would like to turn this into a politicians versus doctors battle instead of confronting the real changes necessary to make patients safer in our hospitals."