Hospitals are experiencing higher patient death rates as a direct result of nursing cutbacks, according to a study of hospitals in England and eight other countries.
Data from 300 European hospitals shows that every extra patient added to a nurse's workload increases the risk of death within a month of surgery by 7%.
The level of training the nurse had undergone also had an impact, the study said, with university degrees going a long way towards making up for reduced staffing levels.
A 10% increase in the proportion of nurses holding a bachelor degree was associated with 7% lower surgical death rates, the findings published in The Lancet journal revealed.
Since September last year, every newly-qualified nurse in the UK has had to possess a university degree.
Figures for 30 English hospitals showed that on average every one of their nurses looked after around nine patients, which is one more than professional bodies would like.
Spain appeared to have the most overworked staff, with an average 12.7 patients per nurse. But in Spain every nurse had a bachelor degree, compared with only 28% in England at the time the data were collected in 2009-10.
In some other countries the patient-to-nurse ratio was significantly smaller. Norway had a ratio of 5.2 to one, the Irish Republic 6.9, the Netherlands seven and Finland and Sweden 7.6.
Lead researcher Professor Linda Aiken said: "Our findings emphasise the risk to patients that could emerge in response to nurse staffing cuts under recent austerity measures, and suggest that an increased emphasis on bachelor's education for nurses could reduce hospital deaths."
The study analysed information on more than 420,000 patients admitted to hospitals in Belgium, England, Finland, the Irish Republic, the Netherlands, Norway, Spain, Sweden, and Switzerland.
Researchers compared nurse workload and education and patient outcomes, taking into account the age and sex of patients, types of surgical procedure, chronic conditions, and the kind of technology available in a hospital.
The overall percentage of surgical patients who died within 30 days of admission was low, ranging between 1% and 1.5% per country. In England, the average rate was 1.4%.
Peter Carter, chief executive of the Royal College of Nursing (RCN), said: "It is worrying to see that researchers found the mean ratio of patients to nurses in England is above eight, as we know that this can compromise patient safety.
"The RCN has also expressed concern at the skills mix in UK hospitals as trusts get rid of more senior nurses to save money, meaning there is far less experience on many wards, and the full extent of this will be revealed in our upcoming Frontline First report."
Health Secretary Jeremy Hunt has said the Government would not introduce a legal minimum because staff requirements were a "different number for different wards".
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Begg was released from Guantanamo Bay in January 2005 
