Two accident and emergency (A&E) units in London are to be downgraded, Health Secretary Jeremy Hunt has announced.
The units at Central Middlesex and Hammersmith will be replaced with 24-hour urgent care centres.
Mr Hunt also said Ealing and Charing Cross hospitals would continue to have an A&E service "even if it is in a different shape or size".
Labour said this "amounted to spin which masked their inevitable downgrading to urgent care centres".
Under the Shaping a Healthier Future programme four A&E units were under threat.
In a statement in the Commons, Mr Hunt accepted the findings of the Independent Reconfiguration Panel review.
The group recommended changes to the A&E departments at Hammersmith and Central Middlesex hospitals should take place as soon as practicable but said further work was required for Ealing and Charing Cross.
Under the plans, nine hospitals in north-west London will be redesigned so the most serious emergencies can be dealt with at A&Es in Hillingdon, Northwick Park, West Middlesex, Chelsea and Westminster or St Mary's hospitals.
Mr Hunt said: "Improvements in emergency care alone should save around 130 lives per annum and the transformation in out-of-hospital care will save many more, giving north-west London probably the best out-of-hospital care anywhere in the country."
He said he wanted to end the uncertainty around the future of Ealing and Charing Cross.
Mr Hunt said any changes as a result of the programme should be implemented by local commissioners following "proper" talks with the public.
Shadow health secretary Andy Burnham said the decision not to close the A&E units represented a minor concession at a time of "brutal surgery" on west London's NHS.
He said the changes were primarily about "saving money, not saving lives".
Addressing Mr Hunt in the Commons, Mr Burnham said: "You talk of their A&Es being of a different size and shape.
"Isn't that just spin for saying that these units will be downgraded and become urgent care centres? Or are you giving them a permanent reprieve?
"If you can't answer those questions directly I'm afraid local people in those areas will take what you have said as just weasel words."
The health secretary said Labour should be "shouting from the rooftops" to support the proposals as they would mean more emergency doctors, more critical care doctors and more psychiatric support, and were supported by the medical directors of all nine trusts affected.
The Department of Health said the changes to A&E at Hammersmith and Central Middlesex hospitals would be made after the winter.
Under the plans, £80m will be spent on both Ealing and Charing Cross hospitals, which will have A&E units open 24 hours a day.
These will have senior doctors and nurses and other emergency care professionals; access to specialist consultant opinion, social care and psychiatry; a range of diagnostic services including pathology and radiology, and the ability to admit people to hospital.
Mr Hunt said resources being taken out of some acute services would be used to give "better and safer" services.
He said an example of changes having a positive impact was stroke services in north-west London, which have been centralised in Charing Cross and Northwick Park, resulting in stroke mortality rates in London halving.
'Continue to fight'
The Labour leader of Ealing Council, Julian Bell, said: "We've been told the maternity unit has been closed - you can't have your baby at Ealing Hospital; blue light ambulances can't come - that in my book is not an A&E and it's not a major hospital.
"It's a sad day and I'm very concerned for the residents of Ealing."
The Liberal Democrat MP for Brent Central, Sarah Teather, said it would be vital for health managers to ensure Transport for London made sure the necessary new travel patterns could be accommodated.
Former shadow health minister Diane Abbott said it was important that "ordinary people" supported the plans.
"Londoners are particularly cautious about these reconfigurations because of historic problems about access to GPs, because of the many excluded communities for whom A&E is their primary care, and because the institutions are often major employers in their area," she said.
Andy Slaughter, Labour MP for Hammersmith and secretary of the Save Our Hospitals campaign, said: "There will be no A&E at Hammersmith Hospital in one of the most deprived areas of London and there are no promises to keep the beds and services at Charing Cross open.
"We will continue to fight these closures until we have a council and a government that will listen to local people and keep our excellent hospitals open."
On Monday, the Court of Appeal ruled Mr Hunt did not have power to implement cuts at Lewisham Hospital in south-east London.
During the summer, a High Court judge ruled Mr Hunt acted outside his powers when he decided the emergency and maternity units should be cut back and the appeal court backed that decision.