Question to the HM Treasury:

To ask the Chancellor of the Exchequer, whether HM Treasury has received a costed plan for migration of government systems to post-quantum cryptography; and whether provision has been made for it in departmental settlements to 2029-30.

Planning for the migration to post-quantum cryptography is expected to be completed by 2027, highest-priority systems migrated by 2031, and all remaining systems transitioned by 2035. Departments will be advised to consider this in spending review planning.