Travellers should exercise increased caution in the United Kingdom following the raising of the national terrorism threat level to severe in early May 2026, indicating that a terrorist attack is judged to be highly likely. The Joint Terrorism Analysis Centre cited both Islamist and right-wing extremist activity, including a recent antisemitic stabbing attack in north London that wounded two people. Demonstrations occur periodically in central London and other major cities and may turn disruptive without warning. Travellers should remain vigilant in crowded public spaces, transport hubs, tourist locations, and places of worship, follow instructions from local authorities, and avoid demonstrations. Routine policing and emergency services remain fully operational throughout the country.