Question to the Ministry of Defence:

To ask the Secretary of State for Defence, how long the vanguard-class submarines have been on patrol at sea on average in each of the last 10 years.

Answered by Leo Docherty - Minister of State (Ministry of Defence) (Minister for the Armed Forces)

The Royal Navy has successfully maintained Operation RELENTLESS, the Continuous At Sea Deterrent, for an unbroken 55 years. We do not disclose details of the Operation, including the duration of time spent at sea, as such information could be used to undermine the security and capability of the mission and our personnel.

Question to the Ministry of Defence:

To ask the Secretary of State for Defence, what recent estimate he has made of the cost to the public purse of Trident renewal in the period between 2023 and 2050; and what proportion this would be of total Government spending in that period.

Answered by James Cartlidge - Minister of State (Ministry of Defence)

As the replacement warhead programme is in its preliminary phases, it is too early to provide cost estimates for the programme. In the absence of these estimates, it is not possible to express deterrent renewal spend as a proportion of overall Government spending.

Question to the Ministry of Defence:

To ask the Secretary of State for Defence, how much has been spent on the Dreadnought programme.

Answered by James Cartlidge - Minister of State (Ministry of Defence)

As of 31 March 2023, £14.7 billion had been spent on the concept, assessment, and early delivery phases of the Dreadnought Programme.

Question to the Ministry of Defence:

To ask the Secretary of State for Defence, what recent estimate he has made of the total lifetime cost of the Trident renewal programme.

Answered by James Cartlidge - Minister of State (Ministry of Defence)

The Dreadnought submarine programme remains within overall budget and on track for the first of class, HMS Dreadnought, to enter service in the early 2030s.

Inflation has remained higher than expected for an extended period and had an adverse impact on the cost forecasts for this programme when compared to the forecasts from a year earlier.

As the programme is in its preliminary phases, it is too early to provide cost estimates for the replacement warhead programme.

Question to the Ministry of Defence:

To ask the Secretary of State for Defence, what recent assessment he has made of the impact of recent trends in inflation rates on (a) the total lifetime cost of and (b) expenditure over the next five financial years on the Trident renewal programme.

Answered by James Cartlidge - Minister of State (Ministry of Defence)

The Dreadnought submarine programme remains within overall budget and on track for the first of class, HMS Dreadnought, to enter service in the early 2030s.

Inflation has remained higher than expected for an extended period and had an adverse impact on the cost forecasts for this programme when compared to the forecasts from a year earlier.

As the programme is in its preliminary phases, it is too early to provide cost estimates for the replacement warhead programme.

Question to the Ministry of Defence:

To ask the Secretary of State for Defence, what the timescale is for the replacement of each of the Vanguard class submarines.

Answered by James Cartlidge - Minister of State (Ministry of Defence)

The programme to build four ballistic missile submarines to replace the current Vanguard Class remains on track to deliver the first boat in the Dreadnought Class, HMS Dreadnought, into service in the early 2030s.

The planned in-service dates for Royal Navy submarines are withheld as disclosure would, or would be likely to, prejudice the capability, effectiveness, or security of the Armed Forces.

Question to the Ministry of Defence:

To ask the Secretary of State for Defence, how many Vanguard class submarines are deployed to provide continuous at sea deterrence.

Answered by James Cartlidge - Minister of State (Ministry of Defence)

The Royal Navy has provided the Continuous At Sea Deterrent for an unbroken 54 years with Operation RELENTLESS. However, we do not disclose these details for operational security reasons as to do so could or would, or would be likely to, prejudice the capability and security of the Armed Forces.

Question to the Ministry of Defence:

To ask the Secretary of State for Defence, when each Vanguard class submarine has been out of service.

Answered by James Cartlidge - Minister of State (Ministry of Defence)

The Royal Navy has provided the Continuous At Sea Deterrent for an unbroken 54 years with Operation RELENTLESS. However, we do not disclose these details for operational security reasons as to do so could or would, or would be likely to, prejudice the capability and security of the Armed Forces.

Question to the Ministry of Defence:

To ask the Secretary of State for Defence, how many of the Vanguard class submarines are out of service.

Answered by James Cartlidge - Minister of State (Ministry of Defence)

The Royal Navy has provided the Continuous At Sea Deterrent for an unbroken 54 years with Operation RELENTLESS. However, we do not disclose these details for operational security reasons as to do so could or would, or would be likely to, prejudice the capability and security of the Armed Forces.

Question to the Ministry of Defence:

To ask the Secretary of State for Defence, what recent estimate he has made of the cost of replacing each Vanguard class submarine under the Trident nuclear programme.

Answered by James Cartlidge - Minister of State (Ministry of Defence)

Replacing the Vanguard Class, the Dreadnought submarine programme remains on track to deliver to schedule and within the original £31 billion plus £10 billion contingency budget made in the Strategic Defence and Security Review 2015.

Question to the Ministry of Defence:

To ask the Secretary of State for Defence, what the projected whole life costs for the Dreadnought programme were in (a) 2022 and (b) 2023.

Answered by James Cartlidge - Minister of State (Ministry of Defence)

I refer the right hon. Member to my letter to him dated 25 October 2023.

A copy of the letter was placed in the Library of the House.

Question to the Ministry of Defence:

To ask the Secretary of State for Defence, when his Department plans to announce the in-service date forecast for the Dreadnought project.

Answered by James Cartlidge - Minister of State (Ministry of Defence)

The planned in-service dates for Royal Navy submarines are withheld as disclosure would, or would be likely to, prejudice the capability, effectiveness, or security of the Armed Forces.

Question to the Ministry of Defence:

To ask the Secretary of State for Defence, what the projected whole life costs of the Dreadnought programme (a) were originally and (b) are as of 12 September 2023.

Answered by James Cartlidge - Minister of State (Ministry of Defence)

I will write to the right hon. Member with the detail requested once it has been collated, and a copy of my letter will be placed in the Library of the House.