McCallum said more than 750 Russian diplomats had been expelled from Europe since Russia’s invasion of Ukraine, many of them spies.
This has affected the capabilities of Russian intelligence, he said, adding that diplomatic visas have been denied to people considered by Britain and its allies to be Russian spies.
Russian state actors have resorted to proxies such as private intelligence agents and criminals to do “their dirty work,” but this has made it easier to influence and disrupt the professionalism of their operations.
Mr. McCallum has spoken publicly before about threats from Russia and Iran, but he has never criticized Moscow so sharply before.
In a previous public speech, he mentioned 10 plots against Iran in the UK. That number has now doubled, meaning Iran’s state activities remain unfazed by threats of arrest.
He said: “We have a conspiracy here in the UK following the 2022 murder of 22-year-old Mahsa Amini, who died in Iranian police custody after being arrested on suspicion of breaching regulations requiring women to wear headscarves. We’ve seen it happen at unprecedented speed and scale.”
He added that as the war continues in the Middle East, MI5 will remain “as alert as possible to the risk of increased or escalation of attacks by the Iranian state in the UK”.
In both cases, in Russia and Iran, MI5 bosses emphasized that accredited diplomats were increasingly turning to underground criminal networks because it was difficult or almost impossible to carry out such actions.
Speaking about China, he said its economic relationship with the UK had helped underpin its security.
But he later told reporters that the Chinese Communist Party (CCP) had a program to steal data and information and that “we have seen 20,000 obfuscated approaches by China to individuals.”
