A FORMER top spy has denied that UK intelligence services have snooped on the activities of mainstream pro-independence parties.

Ciaran Martin, former head of the National Cyber Security Centre, part of GCHQ, said he could not see how a warrant for spying on “anybody seeking peaceful, political change through lawful means” would get past a judge or a Cabinet minister.

Speaking with the Herald on Sunday, Martin said: “Hand on heart, the intelligence services are not a means of suppressing legitimate domestic political activity.”

It comes after extraordinary claims from former SNP MSP Campbell Martin (below), who said MI5 agents had “captured and controlled” the party.

The National: Campbell Martin

He said: “The SNP is completely compromised. It has been captured and controlled by the British state.

“The difference between those early days of the Scottish parliament and today, is that the British state assets in the SNP have, over the intervening years, risen through the ranks and now hold senior positions that have allowed them to influence party policies and direction, such as adopting a lack of urgency in delivering independence.”

READ MORE: SNP government infiltrated by British agents, ex-MSP claims

Asked about whether spy agencies could snoop on parties like the SNP, the former GCHQ chief said: “The way the law is framed I can’t see how a warrant could get past a judge for anybody seeking peaceful, political change through lawful means, and I doubt it would get past a Cabinet minister.”

As well as his career in intelligence, Martin also led civil service negotiations with the Scottish Government prior to the 2014 independence referendum campaign during his time as constitution director at the Cabinet Office.

Speaking about the risks of cyberwarfare tactics being used by hostile states against the UK, Martin said there had been “some” activity during the indyref campaign, adding: “But as far as I know – and I would know – it was very peripheral. I don’t think it could have impacted anyone’s vote.”

He said states like Russia would be “interested” in exploiting divisions on the Union to expose “fissures” in UK politics.

“The Russians are no more and no less interested in Scotland and questions of separation and union than they are in other fissures in British politics,” he said.

READ MORE: Police Scotland reveal position on spying powers amid SNP MI5 claims

“They’re interested in division. Are they interested in fissures in British politics? Yes. Is the union versus separation one of those fissures? Yes. So are they interested in it? Yes.

“I couldn’t stand behind an assertion that there’s a systematic campaign fixed on that issue from any foreign actor. There may be, and there may be one in the future.

“This isn’t a warning. It’s just a statement of the obvious as they’re interested in exploiting divisions. There’s no evidence that they’re acutely or more particularly interested in exploiting this one than they are a bunch of other ones.”

The National: Vladimir Putin

In terms of the Kremlin spying on Scotland, he adds: “Would a hostile foreign actor be interested in the machinations of various politicians in Holyrood or Stormont as well as Westminster? The answer to that is ‘yes, they would actually’.

“At least, they’d be interested enough to go and acquire some data and see if there was anything interesting there. So the espionage risk is big.”

His comments come amid a major cyberattack against the British Library in London, which has paralysed the organisation for months – but he revealed how hackers also took on smaller targets like a bus service charity in Orkney.

Martin said: “It [the British Library] hasn’t been properly working for three months.

“Its main catalogue has gone offline. It’s got 170 million items. They’ve no way of knowing what’s in the catalogue.”

He added: “The criminals knew what they were doing. They asked the British Library for £600,000 as it’s a big publicly-funded institution, but demanded £1,000 in Orkney. They research. To say they’re amoral is an understatement.”