Dylan Earl, 20, appeared at London's Westminster Magistrates' Court on Saturday charged with two offences under the National Security Act over "activity likely to benefit Russia", according to court records.
One of the two charges alleges Earl assisted a foreign intelligence service, including by agreeing to undertake the "research and reconnaissance of targets, and attempting to recruit individuals to assist with such activity".
The other alleges Earl engaged in preparations for "an act endangering the life of a person or an act creating serious risk to the health or safety of the public in the United Kingdom".
Earl was also charged with aggravated arson in relation to a commercial premises in London.
Three other men have also been charged with aggravated arson: Paul English, 60, and Nii Kojo Menash, 21, who appeared in court on Monday, and Jake Reeves, 22, who appeared in court on Friday.
They have not yet been asked to enter a plea.
While we must let the judicial process run its course, I am deeply concerned by allegations of British nationals carrying out criminal activity on UK soil to benefit the Russian state.— David Cameron (@David_Cameron) We will use the full weight of the criminal justice system to hold anyone found guilty of…April 26, 2024
Britain's Crown Prosecution Service said in a statement the arson charges related to "an arson attack on a Ukrainian-linked commercial property in March 2024".
Relations between Russia and Britain have long been strained, and have deteriorated further since Moscow's full-scale invasion of Ukraine in February 2022.
British Foreign Minister David Cameron said he was "deeply concerned" by the allegations in the case.
"We will use the full weight of the criminal justice system to hold anyone found guilty of crimes linked to foreign interference to account," he wrote on social media platform X.
Commander Dominic Murphy, Head of the Metropolitan Police's Counter Terrorism Command, called it a "highly significant moment and investigation for us".
"Not only are the charges that have been authorised by the CPS extremely serious, but it is also the first time that we have arrested, and now charged anyone using the powers and legislation brought in under the National Security Act," he said.
Reeves has also been charged with agreeing to accept a material benefit from a foreign intelligence service.
He appeared at Westminster Magistrates' Court on Friday alongside Dmirtrijus Paulauskas, 22, who was charged with failing to disclose information to police about terrorist acts.
All five men are due to appear in court at the Old Bailey on May 10.
