The number of investigations into hostile state threats being carried out by counter-terror police has “quadrupled” in the last two years, a senior officer has said.

Matt Jukes, head of counter-terrorism policing, described the workload as “unprecedented” and said it marked a “really significant shift” in focus for teams primarily working on terror probes.

“Missions outside of terrorism” now account for around 20% of casework in the wake of Russia’s invasion of Ukraine, to tackle state threats, espionage and probe war crimes, he said.

His comments came as he revealed several terror plots foiled at the last minute in Britain in 2022 were “close calls”, describing them as “goal line saves” because would-be attackers had picked targets and were gathering weapons when officers intervened.

While fighting terrorism is still the “majority” focus, tackling hostile state activity was a “growing part” of work for counter-terror police due the range of threats now faced in the wake of Russia’s invasion of Ukraine, Mr Jukes told reporters at Scotland Yard on Thursday.

He said: “We are shifting, in part, our focus from an exclusive attention to the terrorist threat to a really significant shift in focus on the threat from foreign states.

“For counter terrorism policing that means, at present, that around 20% of our casework is focused on missions outside terrorism.

“That means countering state threats, investigating war crimes and working with MI5 and other partners to address espionage.”

The number of investigations focused on state threats has “quadrupled in recent years”, he said, adding that this referred to “dozens” of cases over the last two years, not “hundreds”.

But he stressed how “scores” of officers could be working on hostile state threats because of the “intensity” of the investigations, adding that the nature of the cases was “palpably different” from terror probes.

Last year the boss of MI5 laid bare the “very real threat” posted by hostile states and set out in stark language the dangers from Russia, China and Iran.

The security agency’s director general Ken McCallum revealed in a speech in November that there had been at least 10 potential plots since January last year by Iranian intelligence services to kidnap or kill British or “UK-based” people considered “enemies of the regime”.

That number now stands at 15, Mr Jukes said, adding: “We have had to respond to very real concerns about the potential threats projected from Iran against people based in the UK.”

Officers are also looking into reports of the alleged presence of “so-called Chinese overseas police stations”.

Mr Jukes said: “I want to be absolutely clear that any attempt to intimidate, to harass or to harm individuals who are UK nationals, or who have made the UK their home, won’t be tolerated.

“At present we’ve got no criminal evidence identified in the UK yet.

“Attempts to set up shop to act outside the conventions of international law enforcement are not acceptable, and they will be stopped. We’ve got the resources to do that.”

Meanwhile, police are continuing to gather evidence of potential war crimes to pass to the International Criminal Court.

So far 100 reports are being considered by officers from people across the UK about the war in Ukraine, Mr Jukes said.