Self-monitoring of blood glucose levels is essential for people with type 1 diabetes and for many with the more common type 2 diabetes, so they can adjust their treatment levels.

Failure to do so can lead to conditions such as hypoglycaemia and ketoacidosis, and if left unmanaged in the long-term can result in serious complications that can require amputations, or cause blindness or stroke.

Blood monitoring and treatment adjustment is also necessary for many people with diabetes to go about everyday activities, such as eating and exercising, safely.

NHS England said that all doctors and pharmacists had been told not to restrict access to testing strips. However, many of the respondents to Diabetes’ UK survey, which consulted 2,000 people with diabetes, said that their GP had told them restrictions were in place because of policies issued by local health managers.

Barbara Young, chief executive of Diabetes UK, said that restricting access was not only causing distress, but would also create a problem for the NHS in the long term, as complications caused by lack of monitoring mounted up. Diabetes already costs the NHS around £10bn annually.