MI5 - Security Service

The UK's Threat Level System

The UK Government's counter terrorism strategy opens in a new window aims to reduce the risk from international terrorism, so that people can go about their business freely and with confidence. While the current terrorist threat presents many challenges, public safety is our absolute priority. The Government can never guarantee that attacks will not happen in the future, but its security effort is dedicated to reducing the risk as much as possible.

Assessments of the level and nature of the threat from international terrorism are made by the Joint Terrorism Analysis Centre (JTAC); the Security Service is responsible for setting the threat levels from Irish and other domestic terrorism both in NI and GB.

Threat levels in themselves do not require specific responses from the public. They are a tool for security practitioners working across different sectors of what we call the Critical National Infrastructure opens in a new window (CNI) and the police to use in determining what protective security response may be required. By its very nature, intelligence cannot be revealed completely and there will always be limitations to what we can say about security and the responses we have planned.

Previously, the Government did not make public the way in which this system works or the national threat level that emerges from it. Since 2006, information about the national threat level has been available on the MI5 and Home Office websites. In September 2010 the threat levels for Northern Ireland-related terrorism were also made available.

Share this information? (all open in new windows)