Bulgarian national Tihomir Ivanov Ivanchev is accused of "conspiring to collect information intended to be directly or indirectly useful to an enemy", the Met Police said.

That information was allegedly collected with a "purpose prejudicial to the safety and interest of the state", Scotland Yard added.

Ivanchev, who has been living in Acton, west London, has been remanded in custody and is due before Westminster Magistrates' Court on Wednesday.

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The 37-year-old was arrested on 7 February as part of an ongoing investigation led by the Met's Counter Terrorism Command.

He was bailed and then charged on Tuesday.

"A sixth suspect was identified and arrested as a result of enquiries made following the previous five arrests in this investigation, and working with the Crown Prosecution Service, a charge has now been brought," said Commander Dominic Murphy, who leads the Met's Counter Terrorism Command.

"Mr Ivanchev has the right to a fair trial, and we would therefore urge people not to publish anything - on social media or in news media - that creates a substantial risk of seriously prejudicing these active criminal proceedings."

The other defendants - three men and two women - are accused of conspiring to gather information that would be useful to an enemy between August 2020 and February 2023 and have previously appeared at the Old Bailey.

They are Orlin Roussev, 46, Bizer Dzhambazov, 42, Katrin Ivanova, 32, Ivan Stoyanov, 32, and Vanya Gaberova, 29.

Their trial, which is expected to last four months, is due to begin in October.