Labour is promising to spend more on the NHS in England than the Tories if it wins the general election.
The NHS budget would rise to £155bn by 2023-24 - £6bn more than the government promised the front-line budget would reach by that stage when it set out its five-year plan last year.
Labour said the money would cut waiting times and boost mental health services.
But the Tories said Labour's plan for a shorter working week would eat into the funding due to the need for more staff.
Health Secretary Matt Hancock said the working hours policy, announced at Labour's annual conference in September, would "cripple our economy and cost the NHS billions every year".
But Labour said a 32-hour working-week would be phased in over 10 years so would not have the impact on NHS budgets claimed by the Tories, and it would also be offset by gains in productivity.
Announcing his party's flagship election policy at the Royal Society of Medicine, shadow health secretary Jonathan Ashworth said after a "decade of underfunding and cuts" waiting lists had risen to "record levels".
"Only Labour has a plan to rescue the NHS," he added.
Shadow Chancellor John McDonnell said Labour's policy of taxing the "richest in society" and reversing cuts to corporation tax would release money to spend on healthcare.
Lib Dem health spokeswoman Luciana Berger said: "Labour's announcement completely misses the point.
"They are ignoring the fact that Brexit is the biggest threat to the NHS."
Labour's proposals were welcomed by NHS leaders.
Niall Dickson, chief executive of the NHS Confederation, which represents managers, said the pledge represented a "significant extra investment" on top of what has been set by the government.
"If used wisely, it would help to transform services and retain front-line staff."
Isn't NHS funding already going up?
During the summer of 2018, the Theresa May government announced a five-year funding settlement for the front line of the NHS in England.
It also meant more money for other parts of the UK - under a system known as the Barnett Formula the devolved nations get the same percentage increases in areas like health - although it is up to Scotland, Wales and Northern Ireland to decide where that is spent.
In England it means the budget for NHS England will be £20bn more in 2023-24 than it was in 2018-19 once inflation is taken into account - a rise of 3.4% a year on average during the period.
Labour has promised to top this up by £6bn by 2023-24 - an annual rise of 3.9% on average over the coming years.
But this front-line budget - £121bn this year - does not cover the entirety of health spending.
Another £18bn is being spent on other areas, including training staff, building projects and public health schemes like stop-smoking services.
Read more of the BBC's Election 2019 coverage here:
Labour has promised to increase these too. The most significant rise will be in the capital budget - for buildings, equipment and infrastructure. This year £7bn is being spent in this area after Boris Johnson increased the budget by £1bn shortly after he became prime minister.
Labour says by 2023-24 the budget will top £10bn a year - a sum health academics have argued is needed to deal with the backlog in repairs and bring spending in line with other wealthy nations.
The Tories have yet to set the budgets for these areas all the way through to 2023-24, although they have said investing in buildings and infrastructure is a priority.
What would Labour's extra money pay for?
In terms of the front-line budget, Labour says the extra £26bn in real terms by 2023-4 they will be investing will help reduce waiting times in A&E and for routine operations such as knee and hip replacements - both targets for how long patients should wait have been missed for the last few years.
They are also prioritising mental health, promising to fund more counselling services for schools, community mental health hubs and crisis teams.
The wider increases in the overall health budget will help fund the return of the bursary for nurses and midwives to fund their time spent studying at university - the government scrapped these in 2017 - while they will also benefit from the Labour policy of scrapping tuition fees.
Labour believes this will help address the shortage of nurses in the NHS.
The party also wants to increase the number of GP training places from 3,500 a year to 5,000.
Free prescriptions and hospital car parking will also be introduced.
How do Labour's plans differ from the Conservatives?
What is quite remarkable is just how similar the Tories and Labour are in terms of many of the areas they are focusing on.
Both are looking to increase the budget by more than it has been in recent years - albeit Labour are promising 4% more by 2023-24 for the front line.
Setting aside free prescriptions and car parking, which are not Tory policies, both parties are prioritising training extra staff and investing in new buildings and equipment
Last week the Tories too pledged extra training places for GPs, saying they wanted to recruit an extra 6,000 GPs.
The prime minister has also promised there will be 40 major hospital building projects in the next decade - although only six have been given a guarantee of funding so far.
The Liberal Democrats are yet to give much detail about their policies - although they have promised a penny on income tax will be introduced, which will raise extra money for mental health, public health and social care.
Do you have any questions about the forthcoming election?
In some cases your question will be published, displaying your name, age and location as you provide it, unless you state otherwise. Your contact details will never be published. Please ensure you have read the terms and conditions.
Use this form to ask your question: