London police arrest 139 protesters outside US Embassy over Palestine Action ban

London’s Metropolitan Police arrested at least 139 people during a demonstration outside the United States Embassy in Nine Elms on October 31, 2026, after protesters gathered to express support for Palestine Action, an organisation proscribed under British terrorism legislation. Police said most arrests involved suspected offences relating to support for a banned organisation, with officers continuing enforcement activity after the reported total was reached. The demonstration was organised by Defend Our Juries, a campaign group challenging the government’s decision to ban Palestine Action. The arrests took place days before the United Kingdom Supreme Court is due to consider a legal challenge concerning the proscription on November 4.

Hundreds of demonstrators participated in the gathering, according to organisers, with many displaying placards supporting Palestine Action and criticising Israel’s military operations in Gaza. Police had warned before the protest that participants could face arrest if they engaged in conduct amounting to an offence under the Terrorism Act. The campaign organisers accused authorities of criminalising peaceful political expression, while the Metropolitan Police maintained that its officers were enforcing legislation governing support for proscribed organisations. The confrontation has intensified scrutiny of the relationship between national-security powers, freedom of expression and the legal status of protest movements in Britain.

What happened outside the US Embassy in London on October 31, 2026?

Demonstrators gathered outside the United States Embassy in Nine Elms, southwest London, on Saturday to express opposition to the proscription of Palestine Action. The event was organised by Defend Our Juries, which has coordinated previous demonstrations involving people openly displaying support for the banned group. Police officers were deployed around the embassy and nearby streets in anticipation of a large gathering. The operation resulted in arrests throughout the afternoon as officers identified conduct they considered to breach the relevant legislation.

At approximately 6.15 pm, the Metropolitan Police reported that 139 people had been arrested. The force said the majority of arrests concerned suspected expressions of support for a proscribed organisation and indicated that additional detentions could follow. The figure represents the police’s confirmed count at that point, rather than a final prosecution or conviction total. Arrested individuals remain entitled to the applicable legal protections and processes for determining whether criminal charges are justified.

Protesters were seen holding signs supporting Palestine Action, while police removed participants from the gathering and transported some to police vehicles. A separate demonstration supporting the group took place outside the United States Consulate in Edinburgh. Police Scotland was examining the circumstances of that event, although the available reporting did not confirm arrests equivalent to those recorded in London. The two demonstrations reflected a coordinated challenge to the government’s proscription policy.

Why is Palestine Action banned under the United Kingdom’s Terrorism Act?

Palestine Action was proscribed in June 2025 under legislation allowing the government to ban organisations meeting the relevant legal criteria for involvement in terrorism. The group, founded in 2020, has carried out direct-action campaigns targeting businesses and facilities it associates with Israel’s military supply chains. Its activities have included property damage at industrial premises and an incident involving military aircraft at a Royal Air Force base. The government has argued that the organisation’s conduct justified proscription under national-security law.

Support for a proscribed organisation can constitute a criminal offence in specified circumstances, including conduct covered by Section 12 of the Terrorism Act 2000. The law does not make every expression of concern about Palestinian rights or criticism of Israel unlawful. Rather, the question is whether particular conduct falls within the statutory offences connected with an organisation that has been proscribed. Police and courts must assess that distinction in individual cases.

The decision to ban Palestine Action has been controversial because campaigners argue that the designation is disproportionate to the organisation’s activities and restricts political expression. The government and police reject the claim that the ban is simply a prohibition on peaceful disagreement with foreign policy. They maintain that the relevant legal framework permits restrictions on support for organisations meeting the statutory criteria. Those conflicting interpretations have become central to the continuing litigation.

Why is the Supreme Court hearing on November 4 important for Palestine Action?

The United Kingdom Supreme Court is scheduled to hear an appeal relating to Palestine Action’s proscription on November 4. The proceedings follow earlier judicial decisions that reached different conclusions about the legality and proportionality of the ban. In February 2026, the High Court found the proscription disproportionate, but the Court of Appeal subsequently upheld the lawfulness of the government’s decision in June. The case is therefore continuing through the judicial process rather than having been conclusively resolved.

The Supreme Court proceedings could have significant implications for the status of the organisation and the interpretation of legal safeguards governing proscription decisions. However, the listing of a hearing does not guarantee that the judges will issue a final ruling immediately. The court may hear legal arguments and reserve judgment for a later date, depending on the issues before it. Until an authoritative decision changes the position, the proscription remains legally relevant.

The timing also gives the October 31 demonstration particular significance. Organisers have sought to draw public attention to the appeal and the consequences of enforcing the ban while the litigation remains active. The government maintains that police must enforce existing law regardless of political disagreement over its merits. The Supreme Court will address the legal questions presented to it rather than determine the guilt or innocence of every person arrested at the protest.

What did the Metropolitan Police say before the London demonstration?

The Metropolitan Police issued a public warning on October 30, making clear that officers would take enforcement action against conduct they considered to constitute support for Palestine Action. Commander Adam Slonecki, who led the operation, said participants had been informed about the legal consequences of supporting a proscribed organisation. He also warned that people involved in organising or facilitating prohibited conduct could face investigation where their activities met the relevant legal threshold. Police presented the operation as an enforcement response to anticipated offences rather than a general ban on demonstrations.

The warning reflected the force’s assessment that some participants were planning to engage openly in conduct they expected would result in arrest. Officers consequently prepared an extensive policing operation around the embassy. The force also argued that repeated demonstrations requiring substantial enforcement resources diverted personnel from other policing responsibilities. Those considerations formed part of its explanation for the scale of the response.

Protest organisers challenged that approach and argued that participants were engaged in peaceful political expression. Their criticism focused on the use of terrorism legislation against people holding placards or taking part in public demonstrations. The disagreement raises questions about the proportionality of enforcement when conduct is expressive rather than violent. Nevertheless, the legal status of each arrest must be evaluated under the legislation currently in force.

How have Defend Our Juries and other campaigners responded to the arrests?

Defend Our Juries condemned the police operation and accused authorities of attempting to suppress opposition to the ban. The organisation said approximately 400 people had participated in the London demonstration, although that figure is an organisers’ estimate rather than a verified official attendance count. Campaigners have also claimed that more than 4,000 people have been arrested for supporting Palestine Action since the proscription took effect. That cumulative figure should be attributed to the organisers unless independently reconciled with official police and criminal-justice statistics.

The protesters’ central argument is that expressing support for a political cause should not automatically be treated as involvement in terrorism. Some participants have deliberately displayed messages expected to attract police attention, making arrest part of their challenge to the current legal framework. Others have criticised the government’s response to the war in Gaza and its relationship with Israel. These motivations may overlap, but they should not be treated as interchangeable with the precise legal elements of the alleged offences.

The Metropolitan Police has maintained that its officers are enforcing an existing statutory prohibition rather than determining national foreign policy. The courts, rather than protest organisers or police commanders, will ultimately interpret the legality of the proscription and the applicable statutory protections. That separation of institutional responsibilities is important because the police operation and the pending Supreme Court appeal address different legal questions. A change in the organisation’s status could affect future enforcement, but its consequences for existing cases would depend on the terms of any ruling.

What happens next after the London Palestine Action protest arrests?

The immediate next steps involve decisions about whether arrested individuals should be charged, released or subjected to further investigation. Police must examine the conduct attributed to each person and determine whether the available evidence supports a suspected offence. The reported figure of 139 arrests does not establish that 139 people will be prosecuted or convicted. Outcomes may differ depending on the evidence and the relevant legal circumstances.

The Supreme Court hearing on November 4 will provide the next major development in the wider dispute over Palestine Action’s legal status. A ruling could clarify the standards governing proscription and the relationship between national-security legislation and protected political expression. However, the court’s final judgment may not be delivered on the hearing date itself. The legal uncertainty will continue until the relevant proceedings are concluded.

The October 31 demonstration has brought the dispute into renewed public focus at the beginning of November. Its significance extends beyond the number of arrests because the proceedings concern how British law defines prohibited support for organisations designated under terrorism legislation. Police have defended their enforcement obligations, while campaigners insist that the ban places unjustified restrictions on peaceful protest. The next judicial decisions will be central to determining how those competing concerns are resolved.