A FORMER SNP minister has blamed “low blood sugar” for an infamous gaffe on live TV that led to his resignation.

Stewart Stevenson said his off-kilter body chemistry meant he had performed below standard, but also blamed officials for not briefing him properly.

“I wasn’t eating, I wasn’t getting enough sleep, I was just utterly, utterly exhausted,” he told Holyrood magazine. 

Mr Stevenson quit as Transport Minister after saying the SNP Government’s response to the big freeze of 2010 was “first class” despite motorists being stranded overnight.

The bitter winter, with long periods of sub-zero temperatures and heavy snows, caused chaos on the country’s road and rail network.

Blizzards forced some people to spend the night in their vehicles in freezing conditions on the M80, A80 and M876 from Glasgow to Stirling.

Even the M8, Scotland’s busiest road, was closed for two days while a 20-mile stretch was cleared of ice and snow.

Despite the obvious problems, Mr Stevenson appeared on BBC Newsnight Scotland to argue the Government’s response was exemplary, causing an outcry.

He then apologised to parliament and blamed inadequate weather forecasts, but failed to mention a Met Office warning issued 12 hours before the problems began. 

Ridiculed as the public face of the crisis, he was forced to resign soon after.

Mr Stevenson, 74, who will stand down after 20 years as the MSP for Banff next year, explained what went wrong in an exit interview with Holyrood magazine.

He said: “I was so run off my feet dealing with the problem that I lost a stone in weight in a single week. 

“I wasn’t eating, I wasn’t getting enough sleep, I was just utterly, utterly exhausted. 

“Hence, when I was on Newsnight, being interviewed, I was a bit inadequately briefed, and my blood sugar was so low I wasn’t performing at the standard I should.”

He went on: “Whatever you might do, you ought to be sure you are fit enough to do it, and that you aren’t saying yes to whatever people want you to do. 

“There will always be more that people want you to do than is seriously possible. 

“If I learned anything from 2010 it’s that I need to think carefully about my own physical and mental preparedness for things that come along.”

Following his departure from the Transport brief after three years, he was brought back into the Government by Alex Salmond a few months later, becoming minister for environment and climate change in 2011 and 2012.