The study compared the NHS with the health systems of 18 similar higher income countries - the original 15 European Union member states, excluding Luxembourg, and the US, Canada, Australia and New Zealand.

Commissioned by the Association of the British Pharmaceutical Industry and developed, researched and written by The King's Fund, the report warned Britain's poor performance - judged by preventable deaths - across several different major disease groups and health conditions including cancer, heart attacks and strokes, should be a serious concern for political leaders and policy-makers.

Researchers also highlighted the NHS had strikingly low levels of key clinical staff, including doctors and nurses, and is heavily reliant on medical professionals trained abroad.

Another key finding was the UK has substantially fewer key physical resources than many of its peers, including MRI scanners and hospital beds.

Prime Minister Rishi Sunak defended the UK health service, saying the government was investing "record sums" to cut waiting lists and "to make sure that the NHS is fit for the future" - pointing to a new scheme for lung cancer screenings as an example.

He admitted to broadcasters that there was "still work to do", but insisted his party could "fix" outstanding issues.

However, Siva Anandaciva, the report's author and chief analyst at The King's Fund, said: "On healthcare outcomes specifically, both for the outcomes that a system can control and those wider measures that rely on services that keep us healthy... we lag behind our peers. We are not by any means where we should be."

Mr Anandaciva said capital infrastructure was "absolutely crying out" for investment, and people from other countries were "really baffled" by the continual lack of investment in this area in the UK.

He said the UK exported a huge amount of nursing talent that is trained in the country and not held onto, instead making up large percentages of medical workforces in countries such as Australia and New Zealand.

Looking ahead, the report suggested UK policymakers should "pick out specific areas of learning and interesting practice" from other healthcare systems, rather than attempt a complete overhaul.

Mr Anandaciva explained: "There are ways in which other countries, like Belgium and Australia, do long-term workforce planning, where they are thinking about the next 10 to 15 years, which we've talked a lot about doing in this country but are still yet to do."

Social care minister Helen Whately told Sky News Breakfast the government is "on track" to recruit and retain over 50,000 new nurses, which was a 2019 Conservative manifesto pledge.

She said part of the long-term workforce plan will aim to increase the number of UK-trained staff, reducing the dependence on staff trained abroad.

Ms Whately said she recognised the UK lagged behind some countries in terms of dealing with major conditions as she highlighted a plan to introduce more integrated healthcare.

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"We know there are conditions and cancers, for example, and other major conditions like heart disease where, if only we could diagnose and pick these things up earlier, we can help people have much better outcomes," she told BBC Radio 4's Today programme.

"And that is one reason we are moving to a more integrated healthcare system, with areas across the country looking across whole populations to be able to intervene earlier and support people more preventively and (provide) earlier treatment.

"It is also why we are developing our major conditions strategy, which is going to be coming forward with better ways of preventing and intervening early to improve people's health."

But Labour's shadow health secretary Wes Streeting put the blame at the door of Downing Street.

"Thirteen years of Conservative government has taken the NHS from its shortest waiting times and highest patient satisfaction in history - delivered by the last Labour government - to where we are today, which is the sick man of Europe, a National Health Service that can no longer claim to be the envy of the world, and one that lets patients down despite the best efforts of staff.

"The longer the Conservatives are in power, the longer patients will wait."