Question to the Ministry of Defence:

To ask His Majesty's Government whether the UK has participated in full in NATO's Locked Shields cyber defence exercise since its inception; and if not, why.

Since 2022, the UK has participated in NATO's Locked Shields cyber defence exercise. From 2025, the UK limited its involvement due to the establishment of the new Defence Cyber and Electromagnetic Force (DCEMF), which created transitional challenges that prevented the coherent commitment of resources. Now that DCEMF has stood up, the exercise is a priority within the UK Defensive Cyber Operating Programme to ensure that UK defensive cyber forces are fully prepared for NATO-led, large-scale warfighting.