Question to the Ministry of Defence:

To ask the Secretary of State for Defence, with reference to the Strategic Defence and Security Review, what the stages will be in the staged investment programme for the Successor submarine programme; and what the estimated timetable for each of those stages is.

In line with normal Ministry of Defence processes, a business case for the additional investment referred to in the Strategic Defence and Security Review is going through the formal approvals process.

Options for the subsequent investment stages, including scope, time and cost are currently under consideration.