DOCTORS have issued a plea over the potentially "catastrophic" impact of a no-deal Brexit on healthcare, warning that it could lead to delays in cancer diagnosis and disrupt treatment for patients with rare diseases.

Dr Peter Bennie, leader of the British Medical Association (BMA) in Scotland, said medics were "increasingly alarmed" by the failure to agree terms of the UK's departure from the European Union with fewer than eight months until the March 2019 deadline.

A report by the BMA said the "worst-case scenario" of a no-deal Brexit would pose "significant ramifications on timely access to new medicines and medical devices" and lead to delays in diagnosis and cancelled operations for cancer patients because the UK would have to source important radioisotopes from outside of EURATOM, the region's nuclear safety and research watchdog.

Meanwhile, it warns the UK would be excluded from the European Rare Disease Network, with implications for around 100,000 Scots living with a rare disease.

The network brings together patients and specialists from 25 EU countries, plus Norway, across 300 hospitals - including 40 NHS facilities - so that individuals in the UK with rare conditions such as bone disorders or childhood cancers can be reviewed by the leading experts in the field, without leaving their home environment.

The report also highlights the risks of fewer doctors and other medical staff "at a time when there are already huge shortages of these roles" due to uncertainty over future immigration status and the mutual recognition of medical qualifications across the EU.

One in 10 UK doctors gained their primary medical qualification in an EEA (European Economic Area) country, and the implications are particularly stark for Northern Ireland where clinicians can move freely to and from the Republic to the south.

A hard border would run the "very real risk" that medical students from Northern Ireland who opted to study and train in the Republic of Ireland "would have would have significant difficulty in returning home to practice medicine in Northern Ireland", while cross-border medical services such as primary care, cancer services and paediatric cardiac surgery - part-funded by the EU - would be under threat.

Dr Peter Bennie, chair of BMA Scotland said: "Doctors are increasingly alarmed by the ongoing failure to secure the kind of deal which will work to the benefit of patients, the medical workforce and health services in Scotland, across the UK and Europe.

"This new paper on a no-deal Brexit describes the consequences of such a scenario as 'catastrophic'. This isn't a warning we make lightly.

"For example, without a deal we risk losing quick and effective access to medical radioisotopes, that are vital for diagnosing particular diseases through nuclear medicine imaging techniques, treatment of cancer through radiotherapy, as well as palliative relief of pain.

"They cannot be stockpiled like other medicines.

"With the delays and uncertainty this may cause to such vital treatment, it is not hard to see why a no-deal Brexit is such a concern."

It comes after warnings from the leader of Scotland's radiologists this week that the service is on "red alert" over a shortage the specialists responsible for reading MRI and CT scans to diagnose cancer.

NHS Highland has also asked local residents to "spread the word" about recruitment opportunities at Belford Hospital in Fort William as they struggle to fill vacancies for a physician and three surgeons.

The report said an end to reciprocal healthcare agreements between the UK and EU would impact on 190,000 UK state pensioners living on the continent who are currently signed up to the S1 scheme, which entitles them to ongoing access to health and social care services.

It adds: "In a worst-case scenario, should the 190,000 UK state pensioners currently signed up to the S1 scheme and living within the EU return to the UK in order to receive care, the additional cost to health services is estimated to be between £500 million and £1 billion per year.

"There would be a requirement for an additional 900 hospital beds, and 1,600 nurses to meet demand."

The BMA has already called for the public to be given a final vote on the Brexit deal and has urged the UK Government to avoid a no-deal scenario.