A&E departments have missing their waiting time targets for the 14th week in a row, with just 87% of patients seen within four hours.
Today's figures come as the first private firm to take over the running of an NHS hospital handed back its contract.
ITV News Correspondent Paul Davies reports:
Following the publication of NHS England figures that show A&E departments last week failed to meet their target of seeing 95% of patients within four hours, George Osborne defended the Conservative Party's NHS record.
Speaking to the BBC, the chancellor said he had put an extra £2 billion into the system.
There are more people than ever working in our health service, we are treating more people than ever, the people within the health service are doing a brilliant job and we are backing them up with increases in the amounts of money going to the health service.
That's not something that has been easy to do, we have had to make difficult decisions - as people are aware - elsewhere in government budgets in order to prioritise the health service.
Responding to the publication of accident and emergency figures from NHS England today that show a failure to meet four-hour waiting targets last week, Labour described it as the "worst in living memory" for the NHS.
These figures show the Tory A&E crisis is intensifying and putting thousands of patients at risk.
Last week was the worst week the NHS has experienced in living memory.
Over 16,000 people had to wait on trolleys in corridors - a staggering 29 per cent increase on the previous worst two weeks earlier.
David Cameron's failure to produce a plan to deal with this cannot carry on. Their complacency is exposing far too many vulnerable people to too much risk.
As NHS England revealed that accident and emergency departments had last week failed to meet targets to see 95% of patients within four hours, it warned that the service would continue to be under pressure for the next few weeks.
Dr Sarah Pinto-Duschinsky said that the flu season meant the NHS had been treating "more patients than than ever before."
Last week, 407,239 patients went to A&E - almost 4,000 more than the previous week and an increase of almost 20,000 on the same week a year ago.
The NHS continues to face unprecedented pressures on its frontline services - with almost 20,000 more A&E attendances than last year - and more than 105,000 people admitted to hospital which is one of the highest figures on record.
The extra £700 million invested has bought 700 more doctors, 4,500 more nurses, creating over 5,000 more beds.
Flu is now at its highest peak for the last three winters which is one of the reasons why over the New Year holiday we continued to treat more patients than ever before.
This means the NHS will continue to be under pressure for the next few weeks. Even at this stage of the winter it is still worth people getting their flu jab if they have not done so, and get advice from their pharmacist for colds, coughs and minor conditions.
Accident and emergency departments in England saw 86.7% of patients within four hours in the week ending January 4, failing to meet the 95% target, NHS England said.
Attendance at Accident and Emergency departments in England has risen by 11% over the past four years, according to data published by the Health and Social Care Information Centre (HSCIC).
Driving the increase was the number of admissions to minor injury units, which has risen at 11 times the rate of population.
The HSCIC's Focus on Accident and Emergency report found over 60,000 per day use A&E services in England and there were 22 million in 2012/13.
NHS England welcomed the report, saying, We know that A&E services are under increasing pressure ... We know that systemic change is needed across our urgent and emergency care system".
NHS national medical director Sir Bruce Keogh has said there is a "feeling that this year is worse" in terms of winter pressures on accident and emergency departments.
Sir Bruce, who is due to publish a report next week on the long-term vision for casualty departments, said: "We have some immediate winter pressures. Winter doesn't come as a surprise. It comes every year and every year we plan for winter and we focus on three areas.
"One is to try and reduce the number of people attending A&E, the second is to help hospitals function in a more efficient way, and the third is to reduce the congestion in hospitals by trying to help hospitals get their patients home.
"There is a feeling that this year is worse."
Keogh insisted the NHS had already taken steps to deal with the expected pressures this winter, including the establishment of 147 urgent care working groups and the distribution of £250 million in September to enable hospitals to prepare.
Accident and Emergency departments in the NHS are facing what may be "our worst winter yet" due to a combination of soaring demand, a shortage of doctors and "toxic" overcrowding on hospital wards, a senior consultant has warned.
Bernadette Garrihy, a member of the board of the College of Emergency Medicine, said doctors were concerned about their ability to provide a "safe and quality service" this winter.
Dr Garrihy said Government measures in trying to deal with the issue amounted to a "drop in the ocean", and called for sweeping changes to help ease the pressure on services.
The senior consultant said part of the problem was caused by people going to casualty departments for problems which could be death with elsewhere and urged patients to consider other options before heading to Accident and Emergency this winter.
Almost two-thirds of patients would be "extremely likely" to recommend their A&E according to a new "friends and family" survey.Read the full story ›
I am determined to give patients a far greater voice within the NHS as a way of highlighting the best and worst of care within our hospitals.
With the ‘Friends and Family’ test, we now have a single measure that looks at the quality of care across the country.
I want the NHS to put patient satisfaction at the heart of what they do and expect action to be taken at hospitals where patients and staff say standards are not good enough.