Question to the Ministry of Defence:

To ask the Secretary of State for Defence, what recent assessment he has made of the potential merits of upgrading the current operating system for the Trident nuclear weapons system to ensure its cyber security.

We continually assess the capability of the United Kingdom's nuclear submarine fleet to ensure its operational effectiveness and to maintain resilience against potential threats.

I am withholding information on the specific systems used by our submarines as disclosure would, or would be likely to prejudice the capability, effectiveness or security of the Armed Forces.