Brexit could have a “potentially catastrophic” impact on the NHS, the authors of a major new report have claimed as they warned they had no confidence the Government was in a position to address the consequences.

Assessing three scenarios – “soft Brexit, hard Brexit, and failed Brexit” – the authors conclude in the Lancet medical journal that each poses a substantial threat to the NHS.

Even a so-called soft Brexit that retains access to the EU’s single market while restricting free movement is likely to have a big impact on health care, they claim.

“The workforce of the NHS is heavily reliant on EU staff,” the authors write. “Financing of health care for UK citizens in the EU and visa versa is threatened, as is access to some capital funds, while Brexit threatens overall economic performance. Access to pharmaceuticals, technology, blood and organs is jeopardised.”

In a withering critique, the researchers add that they have “no confidence” that Theresa May’s Government is yet in a position to address the consequences of Brexit on Britain’s health service, which they predict risks “overwhelming Parliament and the civil service”.

They add: “The future is especially uncertain following the 2017 general election, which left the Government with a minority in Parliament.

“There are deep divisions with the Cabinet and we have no confidence that central Government is yet in a position to address the consequences for health.”

Professor Martin McKee, a member of the team from the London School of Hygiene & Tropical Medicine, said: “Our analysis of how Brexit will affect the NHS, although the UK’s desired outcome remains unclear, is that Brexit in any form poses major risks to almost every part of the NHS, with a ‘no deal’ scenario potentially catastrophic.

”The EU has shown that it recognises many of these threats, and we hope that our paper encourages the UK negotiating team to make health issues a priority.”

After Brexit it will be increasingly difficult for the UK to recruit sufficient NHS and social care staff, according to the research.

Estimates for 2017 suggest that 60,000 people from the EU work in the NHS and 90,000 are employed in adult social care, with a concentration of staff in London and the south east. These regions would be especially vulnerable to labour shortages, said the authors.

Another risk highlighted in the report was the loss of funding to the NHS, both as a direct result of the European money stream being cut off, and indirectly from impacts on the UK economy.

It comes after Sir Vince Cable, the Liberal Democrat leader, warned earlier this month that Ms May’s Brexit plans pose a threat to millions of pounds worth of investment in schools and hospitals across the UK.

Brexit: the deciders Show all 8 1 /8 Brexit: the deciders Brexit: the deciders European Union's chief Brexit negotiator, Michel Barnier Getty Brexit: the deciders French President Emmanuel Macron Getty Brexit: the deciders German Chancellor Angela Merkel Reuters Brexit: the deciders Commission President Jean-Claude Juncker EPA Brexit: the deciders The European Parliament's chief Brexit negotiator Guy Verhofstadt Getty Brexit: the deciders Britain's Prime Minister Theresa May Getty Images Brexit: the deciders Britain's Chancellor of the Exchequer, Philip Hammond PA Brexit: the deciders After the first and second appointed Brexit secretaries resigned (David Davis and Dominic Raab respectively), Stephen Barclay is currently heading up the position PA

An analysis by the party claimed the European Investment Bank (EIB) has provided £380m in investment to schools and £345m in hospitals since 2015 – a vital source of cheap loans for “cash-strapped” local authorities.

“I remain deeply concerned about the effects of leaving the EU on all aspects of the UK’s economic, social and cultural life, including health,” said professor Tamara Hervey – one of the authors of the study from the University of Sheffield.

“If we must leave the EU, I hope this analysis will help interested stakeholders and our elected representatives to hold our government to account to deliver a ‘healthy Brexit,” she added.

Another author, Nick Fahy, a former European Commission staffer who is now at the University of Oxford, said: “Health is often thought to be a purely national matter, relatively insulated from the consequences of Brexit.