Renowned physicist Stephen Hawking delivered scathing assessment of the Conservative Party's handling of the NHS, criticising levels of funding, privatisation of services, and the public sector pay cap.

The 75-year-old scientist, who was diagnosed with motor neurone disease in 1961 and has been reliant on the NHS ever since, did not explicitly name any particular political party, but referred to policies pursued by Conservatives since their 2010 election win.

Hawking's comments were made ahead of a speech at the Royal Society of Medicine on 19 August about how he owes his long life and professional achievements to the health service.

"The crisis in the NHS has been caused by political decisions," Hawking said, reported The Guardian. "The political decisions include underfunding and cuts, privatising services, the public sector pay cap, the new contract imposed on the junior doctors and removal of the student nurses' bursary.

"Failures in the system of privatised social care for disabled and elderly people has also placed additional burden on the NHS."

The author of A Brief History of Time will target Health Secretary Jeremy Hunt directly in his speech, criticising him for citing four studies that were not peer reviewed and ignoring 13 others that contradicted him.

"Speaking as a scientist, cherry picking evidence is unacceptable," Hawking will say. "When public figures abuse scientific argument, citing some studies but suppressing others, to justify policies that they want to implement for other reasons, it debases scientific culture.

"One consequence of this sort of behaviour is that it leads ordinary people not to trust science, at a time when scientific research and progress are more important than ever, given the challenges we face as a human race."

Hunt responded to Hawking's comments on Twitter, writing: "Stephen Hawking is [a] brilliant physicist but wrong on lack of evidence for weekend effect. 2015 Fremantle study most comprehensive ever. And whatever entrenched opposition, no responsible health sec could ignore it if you want NHS to be safest health service in world as I do."

Stephen Hawking
Stephen Hawking at the One World Observatory in New York last year. Getty Images

Hawking was also critical of NHS privatisation, voicing concerns that the money used on temporary workers to alleviate understaffing has benefited private employment firms and fearing the introduction of a "US-style insurance system".

"The huge increase in the use of private agency staff, for example, inevitably means that money is extracted from the system as profit for the agency, and increases costs for the whole country," Hawking said.

"We must prevent the establishment of a two-tier service, with the best medicine for the wealthy and an inferior service for the rest. International comparisons indicate that the most efficient way to provide good healthcare is for services to be publicly funded and publicly run.

"We see that the direction in the UK is towards a US-style insurance system, run by the private companies, and that is because the balance of power right now is with the private companies."

A spokesperson for the Department of Health said in response to the comments: "This government is fully committed to a world-class NHS free at the point of use, now and in the future. That's why we're backing it with an extra £8bn of investment over the next five years.

"Today, there are almost 11,800 more doctors and over 12,500 more nurses on our wards than there were in 2010 and the NHS is seeing 1,800 more A&E patients within the four-hour standard every single day. Despite being busy, the NHS has been ranked as the best, safest and most affordable healthcare system out of 11 wealthy nations, as analysed by the Commonwealth Fund."