MI5 has downgraded the threat level to Britain from Northern Ireland-related terrorism.
The Home Office said the threat had been reduced from substantial to moderate, meaning a terrorist attack was “possible but not likely”.
The UK still faces a “severe” threat from international terrorism, meaning an attack is “highly likely”.
Home Secretary Amber Rudd said: “Despite the change which has been made today, there remains a real and serious threat against the United Kingdom from terrorism and I would ask the public to remain vigilant and to report any suspicious activity to the police regardless of the threat level.”
The decision to reduce the threat level from Northern Ireland to the second-lowest was by taken the security service based on latest intelligence, Ms Rudd added.
The threat level to Northern Ireland from terrorism based in the country itself remains “severe”.
The UK had faced a “substantial” terror threat from Northern Ireland – meaning there was a “strong possibility” of an attack – since May 2016.
Then-home secretary Theresa May said the move reflected “the continuing threat from Dissident Republican activity”.
There are five threat levels – low, moderate, substantial, severe and critical. They are set based on a range of factors including intelligence, terrorist capability, and timescale.