“Turning the Scottish Fire and Rescue Service (SFRS) into a more flexible, modern service has been steady but slow,” said Auditor General Caroline Gardner’s report.

It said real progress has been made integrating the eight former services into a single body.

“The SFRS is now in a good position to complete the process following a deal agreed in April 2018 to harmonise firefighters pay and conditions …” said the report.

“Modernisation is needed to reflect the different risks faced by Scotland’s population since the regional fire services were set up in the late 1940s.

“The SFRS’s running costs are around 12 per cent lower (£266m) than when the services merged five years ago.

“It has also demonstrated strong financial management and board governance.

“But the single service has inherited a capital backlog of £389 million needed to maintain and invest in its property, vehicles and equipment.”

This backlog, said the report, “is insurmountable without a transformation of the service’s current delivery model plus additional investment.”

Gardner added: “The Scottish Fire and Rescue Service has an ambitious vision that involves significant changes to make it a more flexible, modern service.

“It has been working towards this for some time and has taken a cautious and measured approach due to a range of contributing factors.

“It now needs to press ahead with transformation so that it can respond to the changing needs of the public and can address its increasingly unsustainable model of delivery.

“This will take time to achieve and will mean difficult decisions about how the SFRS deploys its people and resources.”