Iran has "ambitions" to kidnap or kill Britons it sees as "enemies of the regime", the boss of MI5 has warned.
Director general Ken McCallum has claimed that the Middle East country "projects threat to the UK directly, through its aggressive intelligence services".
He went on to reveal at least 10 such potential threats have been seen so far this year - which have included death threats to two London-based journalists from Tehran-backed agents over the reporting of the country’s protests.
This comes following news that England are playing Iran in the FIFA World Cup 2022 in Qatar on Monday with thousands of Iranian and English fans expected in the Middle-eastern country.
In a speech given from the security agency's Thames House headquarters in London today, Mr McCallum gave a stark warning that not only does the UK 'face dangers' from Russia and China - it also does so from Iran.
Mr McCallum went on to describe that the UK is in a contest with "adversaries who have massive scale and are not squeamish about the tactics they deploy".
Drawing on a football analogy to hammer home his concerns to Brits, Mr McCallum said Russia "thinks nothing of throwing an elbow in the face, and routinely cheats to get its way, adding that: "They will keep attacking us".
While he stressed that president Vladimir Putin was "not winning" the war in Ukraine, he warned that Chinese authorities are "trying to re-write the rulebook, to buy the league, to recruit our coaching staff to work for them".
While, he said, Iran "will only let people support one team and is prepared to use violence against those who don't toe the line".
As he highlighted Iran providing support to Russia by supplying drones "inflicting misery in Ukraine," he added: "We're alive to the risk of these teams loaning players to each other, amplifying their strengths."
The MI5 boss went on to say that Iran: "Projects threat to the UK directly, through its aggressive intelligence services.
"At its sharpest, this includes ambitions to kidnap or even kill British or UK-based individuals perceived as enemies of the regime.
"We have seen at least 10 such potential threats since January alone. We work at pace with domestic and international partners to disrupt this completely unacceptable activity."
And in his wide-ranging speech, Mr McCallum went on to say that while rising state threats are a "huge challenge" as getting ahead of terror plots was "still the first thing the British public expect of us", he went on to explain that so-called lone wolf terrorists were "fiendishly hard to detect and disrupt".
Since the start of 2017, MI5 and the police have disrupted 37 late-stage terror attack plots - including a further eight since Mr McCallum gave his last update on threats in July last year.
Meanwhile, security services are seeing growing attempts by right-wing extremists to "acquire weapons" - particularly firearms - "well in advance of any specific targeting intent developing", Mr McCallum said.
The MI5 boss went on to that are also growing numbers of right-wing extremist "influencers" which "fuel grievances and amplify conspiracy theories," while adding that terrorism inspired by Islamist ideology still accounts for about three-quarters of MI5's terrorist caseload.
