Of the 16 public sector executives who earn more than the First Minister, 13 of them work in the health service, and it is thought more than 2000 staff earn more than £100,000 a year.

But it has been family doctors, with an average take-home pay of £87,000, who have seen the largest increase over the past decade.

Salaries for contractor GPs – those at surgeries offering a wide range of clinics and services – have risen almost £40,000 since 2002, after the most radical overhaul in a generation of the way doctors are paid.

Just less than one-third of contractor GPs in Scotland now earns more than £100,000 before tax – one in 10 earns more than £125,000. By contrast, the salaries of those employed directly by a practice are a modest £52,912.

In 2004, GPs were offered much greater control over the type of surgery they ran as the NHS sought to create a comprehensive frontline healthcare service. Money was on offer for enhanced services such as cancer clinics, minor surgery, flu jabs and the creation of a register of those at risk from heart disease.

While GPs could generate more income and expenses, they could also, controversially, choose to opt out of offering an out-of-hours service for nights and weekends.

On the face of it, GPs were earning more at a time when it was perceived they were dropping a key service for patients, but family doctors have argued that the new ­contracts have allowed them to respond more precisely to local health needs.

Five years on and the atmosphere has changed. The highest-paid GPs have since been targeted by Alistair Darling, Chancellor of the Exchequer, who has called for a pay freeze for 40,000 senior public servants.

In addition, Scotland’s largest health board is planning to cut spending on nurses by millions of pounds as it battles to balance the books.

NHS Greater Glasgow and Clyde said this week it has exhausted “softer” ways of saving money during the past two years and is having to consider “more radical options” to slash costs. The predicament of the NHS board was widely condemned yesterday.

Jackie Baillie, shadow health secretary, said: “The SNP Government made a deliberate choice to give the NHS its worst financial settlement since devolution. Now we are seeing the consequences.

“It is simply unacceptable that Scotland’s biggest health board should be forced to consider denying patients new treatments or making staff redundant to balance the books. This will inevitably have an impact on frontline patient care.

“The Health Secretary, Nicola Sturgeon, must start to support our doctors and nurses properly and change course before the SNP’s cuts do real damage to the health service and to patient care.”

Royal College of Nursing Scotland’s Professional Officer for Glasgow, Anne Thomson, added: “Quality patient care and frontline services must not be sacrificed for the sake of balancing the books.”