Patients admitted to hospital at evenings and weekends face a postcode lottery as to whether they will have access to consultants and other senior doctors, a report has suggested.
Hospital patients should be seen by a consultant at least once every 24 hours, the Academy of Medical Royal Colleges has recommended.
Mounting evidence suggests that patients are more likely to die if admitted as emergencies in the evening and at the weekend.
The new report calls for health service bosses to ensure that adequate numbers of consultants are provided to enable consultant-led care seven days a week.
It states that hospital patients should be reviewed by an on-site consultant at least once every 24 hours, seven days a week, unless it has been determined that this is not necessary.
While the move is not a "panacea for all patient safety issues", it could improve consistent quality care for patients, the report adds.
Professor Norman Williams, steering group chair and president of the Royal College of Surgeons of England, said: "The standards we recommend in this report reflect the importance of daily consultant-led care and the support that needs to accompany this to ensure that patients receive the very best treatment.
"It cannot be right that over weekends and bank holidays patients may receive a lower standard of care than they would during the week. Clinical staff and managers must work together to reshape hospital services in a way that strengthens the quality of care given to patients regardless of the time of day they are admitted.
"Similar arrangements will be necessary to support patients in the community when discharged at weekends. Ensuring that key staff are available to provide this support will come at a cost. However, this is crucial for the full benefit of seven-day consultant-led care to be realised."
Dean Royles, director of the NHS Employers organisation, added: "We know there will be significant challenges and we can expect some resistance to change. A different way of working requires a pay system that recognises weekends and evenings as normal working times. It needs to be patient care not overtime rates that drive this change forward."