Epsom and St Helier hospitals are to invest at least £2m more a year in new staff in a bid to meet all the new clinical standards developed for London hospitals.
Both hospitals failed to meet some of the standards developed by NHS England London, in conjunction with clinicians and patients - the London Quality Standards.
The standards were developed by NHS England London in 2012-13 to improve the quality and safety of emergency care, following concerns about heightened mortality risks at weekends and high maternal death rates in London compared to the rest of the UK.
Last month, NHS England London published self-assessments, conducted by all London hospitals, as to whether they are meeting the list of 200 standards across adult medicine, A&E, critical care, paediatric emergency services and maternity services.
Neither Epsom or St Helier met the standard requiring consultant involvement for patients considered ‘high risk’ within an hour in acute medicine on any day of the week.
Not all patients on acute medical and surgical units at St Helier were seen and reviewed by a consultant during twice daily ward rounds on any day of the week.
Neither hospital has a consultant on its labour ward 24/7 on any day of the week.
With regards to paediatric emergency and inpatients, St Helier met all bar one standard, while Epsom failed to hit a number - including not having a consultant paediatrician present and readily available during times of peak emergency attendance and activity on any day of the week.
Dr James Marsh, the trust’s joint medical director, said the hospitals had made "some great progress" in improving their performance since last year, but more needs to be done.
He said: "We are performing better than some of the other London hospitals in some areas, and less well in others.
"The data shows the quality of care provided across south west London is relatively even.
"However, we recognise we need to put some changes in place to meet all of the standards and are confident that, in time, we will be able to do so.
"Although no trust in London met all the standards, we know it is possible, and will be working hard to achieve that."
He said each of Epsom and St Helier's clinical areas have identified the resources required to meet the standards over the next few years and are working with their clinical commissioning groups to achieve this.
Dr Marsh added: "As some of these standards require the recruitment of significant numbers of additional staff, particularly consultants, we are planning to invest at least £2m per year in the recruitment and staffing of certain areas."
He said that in some standards where it appears Epsom and St Helier have performed badly, particular criteria in these areas do not apply to the hospitals.
Dr Marsh said: "In critical care, it seems that Epsom does not meet some of the criteria. That’s because in the appropriate circumstances, critical patients would go straight to St Helier for specialist treatment, rather than receive care at Epsom. It is therefore not assessed and is published as though it was not met."
He said the trust has already made a number of improvements to meet the standards.
These include access to 24-hour endoscopy services for emergency patients with a 24/7 consultant; trained and experienced doctors in emergency medicine 24/7; seven days-a-week access to and support from physiotherapy and occupational therapy teams; and all emergency admissions to critical care being seen and assessed by a consultant in intensive care within 12 hours of admission to the critical care unit.
Dr Andy Mitchell, medical director of NHS England London region, said: "We want patients to receive consistently high quality emergency care seven days-a-week, but we know that is not always happening at the moment.
"That is why London’s clinicians are leading the way by developing standards to eradicate the ‘weekend effect’ which could be costing 500 lives a year.
"We are pleased that acute hospitals across London have taken part in the latest self-assessment and have been working hard to meet the standards, resulting in good progress over the last year.
"However, it is clear there is still some way to go.
"For all hospitals to meet all the standards we will need to change the way some services are provided at a local and at a network level.
"London’s CCGs are working on five-year plans which will describe how every hospital will deliver all the standards."