The United States Embassy in the United Kingdom has advised American citizens to exercise increased caution following a rise in the country’s terrorism threat level.

The warning comes after UK authorities raised the national terror alert from “substantial” to “severe,” meaning an attack is now considered highly likely.

In its advisory, the embassy urged Americans living in or visiting the UK to remain alert in public spaces, avoid drawing unnecessary attention, and regularly review their personal safety plans. It also advised extra caution in crowded places such as transport stations, schools, hospitals, places of worship, and tourist areas.

UK security officials said the decision reflects a broader assessment of evolving risks linked to both extremist networks and far-right groups operating within the country.

The heightened alert followed a recent stabbing incident in north London that authorities have treated as a terrorist attack. The incident, which targeted members of the Jewish community, has increased concern about public safety.

A suspect has been charged in connection with the attack and is expected to appear in court for further proceedings later this month.

Officials in the UK emphasized that the upgraded threat level is precautionary and aimed at strengthening public awareness and preparedness rather than causing alarm.

The country had last been under a “severe” terror alert in 2021 following several major security incidents.