Britain will have to tackle Russian aggression for years to come, said the MI5 chief on Wednesday, adding that his agency had blocked more than 100 attempts by the Kremlin to insert suspected spies into the UK since the Salisbury poisonings. Ken McCallum, giving an annual threat update, said state-based threats were increasing and said the UK also faced a heightened direct threat from Iran, which had threatened “to kidnap or even kill” 10 people based in Britain in the past year. The spy chief said Russia had suffered a “strategic blow” after 400 spies were expelled from around Europe following the start of the war in Ukraine, but he said the Kremlin was actively trying to rebuild its espionage network. Britain had expelled 23 Russian spies posing as diplomats after the poisoning of Sergei and Yulia Skripal in Salisbury in 2018, yet since then “over 100 Russian diplomatic visa applications” had been rejected on national security grounds. McCallum accused Russia of making “silly claims” about British activities without evidence, such as that UK was involved in attacking the Nord Stream gas pipelines. But the head of MI5 said “the serious point” was that “the UK must be ready for Russian aggression for years to come”. Iran’s “aggressive intelligence services” were actively targeting Britain and had made “at least 10” attempts to “kidnap or even kill” British or UK-based individuals since January as the regime felt greater pressure than ever before. Last week, the Foreign Office summoned the Iranian deputy ambassador over allegations that two London-based journalists have faced death threats from Tehran-backed agents over the reporting of the protests in Iran. The news channel Iran International took precautionary steps to protect its reporters after being informed by the Metropolitan police earlier this week that it believes there were credible threats to the journalists’ lives. China, McCallum said, was playing “the long game” seeking to cultivate long-term contacts with politicians and intimidating members of the Chinese diaspora, including when a pro-democracy protester “appeared to be the subject of violence” outside the Chinese consulate in Manchester. Turning to terrorism, the MI5 chief said eight “potentially deadly” terror plots were disrupted in the last year, a mixture of Islamist and rightwing terrorism, although none was related to the funeral of the Queen in September. Extreme rightwing terrorists – some of whom are as young as 13 – operated in “a confused soup of hate”, McCallum said, fueled in part by a “growing number of rightwing extremist influencers” from outside the established political system. Such extremists were making further attempts to acquire 3D printed or homemade guns and other weapons – often long in advance of any specific terror threat developing – and McCallum said he believed the ultra-rightwing threat was a problem “that feels like it will endure”. Islamist terror represented “about three-quarters” of the terror caseload, McCallum added, mostly from “radicalised terrorists seeking to conduct low sophistication attacks”. Low sophistication did not mean low impact, however, the spy chief added, citing “the appalling murder” of the MP Sir David Amess a year ago. Detecting such “self-initiated terrorists” was an inherently hard challenge, the MI5 leader continued, and investigators were faced with “the complex mix, often, of extremist ideology with personal grievance and individual vulnerability such as mental ill health”. Earlier this month Andrew Leak, 66, died after staging a petrol bomb attack aimed at migrants in Dover, in an act that police described as terrorism after several days of investigation. Police, he said, had “have difficult judgments to make” about whether an incident constitutes a terror attack and that confused or unclear ideologies were “genuinely a conundrum for us as to how best to manage those risks”. Social media postings from Leak revealed that he wanted to end illegal immigration in the UK and in his final tweet an hour before his attack had threatened to “obliterate Muslim children” and made other threats directed at migrants.