Three people have been charged with showing support for Palestine Action after the group was banned as a terror organisation.
Two women and a man were arrested in Westminster following a protest in central London on 5 July, the Metropolitan Police said.
Jeremy Shippam, 71, of West Sussex, Judit Murray, also 71, of Surrey, and Fiona Maclean, 53, of Hackney in London, were charged with displaying an article in a public place, arousing reasonable suspicion they are a supporter of a proscribed organisation, under section 13 of the Terrorism Act 2000.
The trio are due to appear at Westminster Magistrates' Court on 16 September.
The charges come ahead of a planned protest in support of the group on Saturday afternoon in Parliament Square in London, which organisers expect more than 500 people will attend.
Defend Our Juries, which is organising the demonstration, said protests will continue until a High Court challenge over Palestine Action's ban in November.
Commander Dominic Murphy, head of the Met's Counter Terrorism Command, said: "Anyone who displays public support for Palestine Action, a proscribed organisation, is committing an offence under the Terrorism Act and can expect to be arrested and, as these charges show, will be investigated to the full extent of the law.
"These charges relate to three people arrested in central London on 5 July.
"We are also planning to send case files to the Crown Prosecution Service for the other 26 people arrested on the same day.
"I would strongly advise anyone planning to come to London this weekend to show support for Palestine Action to think about the potential criminal consequences of their actions."
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The latest charges bring the total number of people charged with offences under the Terrorism Act related to Palestine Action to 10 across England, Wales and Scotland, Counter Terrorism Policing said.
Vicki Evans, senior national coordinator for Prevent and Pursue at Counter Terrorism Policing, said: "Our role is to enforce the law where we suspect offences to have been committed and we will continue to do so, without fear or favour.
"At this time, it remains illegal to be a member of or encourage support for the group Palestine Action. This legislation is specific to that group and does not interfere with the right to protest in support of the Palestinian cause.
"Operational plans are in place to ensure this right can be preserved over the coming days with protests expected in several major cities, including London.
"As well as robust plans to respond to activity in support of this proscribed group, resources are also in place to investigate offences that may be identified or reported following such events."
More than 220 people have been arrested at protests across the UK in response to the proscription last month, as part of the campaign coordinated by Defend Our Juries, including on suspicion of membership of, inviting support for and showing support for Palestine Action.
The ban on the group came after two Voyager aircraft suffered around £7m worth of damage at RAF Brize Norton in Oxfordshire on 20 June.
Three days later, Home Secretary Yvette Cooper announced plans to proscribe Palestine Action, calling the vandalism "disgraceful" and saying the group had a "long history of unacceptable criminal damage".
(c) Sky News 2025: Three charged with showing support for Palestine Action