"Terrorists are very likely to try and carry out attacks in Sweden," read the updated FCDO advice. "Attacks could be indiscriminate, including in places frequented by foreigners."
Authorities in Sweden have reportedly disrupted a number of planned attacks and made a number of arrests.
However, a heightened threat of terrorist attacks globally against UK interests and British nationals – from groups or individuals motivated by the conflict in Iraq and Syria – remains, the FCDO added.