Question to the Ministry of Defence:

To ask the Secretary of State for Defence, what percentage optimism bias his Department applied to the Successor Trident programme.

Successor submarine is categorised as "Production of a Platform" for optimism bias purposes. In line with normal Ministry of Defence processes, the optimism bias will be addressed as part of the process of securing approval for the next investment point.

I am withholding information for the current calculations for optimism bias, as the formal internal scrutiny process has not been completed.