DEREK Mackay has likened UK Government ministers to Scotland’s “imperial masters”.

The SNP Finance Secretary joked that in his experience they weren’t up to the job.

Mr Mackay also revealed he walked out of his first meeting with the new Chief Secretary to the Treasury, who then asked him to go easy on him because he was new to the post.

“Poor Rishi Sunak pretty much pleaded with me to give him a chance,” he said.

The Tories said the language was stoking up “extreme elements” of the Yes movement.

The Finance Secretary, who is seen as a potential First Minister, made the cracks in a new interview with Holyrood magazine.

He said: “I’m now onto my third chancellor and as many chief secretaries to the Treasury.

“Like many people, I sometimes have imposter syndrome and I don’t think it’s a bad thing to admit that there are times when I don’t think I’m good enough to do the job.

“I have to say, having met my so called Imperial Masters, I am feeling perfectly apt and perfectly up to the job.”

On meeting Mr Sunak, he said: “I had a recent meeting with the then newly installed chief secretary to the Treasury, Rishi Sunak, and have to say that we did lock horns.

“I was explaining to him how the fiscal framework – that’s the financial arrangements coming from the Scotland Act – was no longer fit for purpose, how it was unravelling because of the experiences we’ve been through and the decisions that the UK Government has taken

“Honestly, I felt that once again, we’ve got a UK minister that is being evasive and not engaging properly with us.

“My experience with David Gauke, Liz Truss and now Rishi is that they don’t treat us as equal partners.

“They are awfully gentlemanly in their conduct, or Rishi is, I’ll give him that, but I’ve been in time after time and told that ‘we’re working on it’ and ‘we’ll get back to you’ and it just isn’t good enough.

“I wouldn’t expect to give those kinds of vague answers and get away with it.

“So, this time, when I felt that I was getting a little bit of pushback, I got up to leave. I left the meeting expressing my displeasure at the attitude of the UK Government towards Scotland.

“He followed me out the door and said he was new to the job and to give him a chance.

“He’s someone I would like to be able to work with, but you know, I’ve met amiable UK ministers before and that means nothing if they don’t deliver on what Scotland wants or needs and that’s what I’ll judge as success.

“I’m not just there representing the SNP, I’m there representing the people of Scotland and the Scottish Government, so, yes, poor Rishi Sunak pretty much pleaded with me to give him a chance.”

Scottish Conservative chief whip Maurice Golden said: “Senior SNP ministers routinely use language like this for no other reason than stoking up the extreme elements in their support.

“Derek Mackay knew exactly what he was doing when he used this phrase. This is typical behaviour from someone who is a nationalist and populist to the core.

“It’s immature politics, and unbecoming for someone in such a senior role.”

A Scottish Government source said: “The entire Tory party longs for a return of the glory days of the British Empire – even dubbing their shambolic Brexit plans 'Empire 2.0' – so it is a little surprising that they have taken offence at something so obviously said in jest.

“Perhaps they are a little sensitive with this coming on a day when their leader has rejected Scotland’s democratic mandate for an independence referendum – despite him losing more than half of his Scottish MPs.”