Question to the Ministry of Defence:

To ask the Secretary of State for Defence, with reference to the press release entitled New Storm Shadow and missile cooperation to boost jobs as UK and France reboot defence relationship, published on 9 July 2025, how the 50,000 strong combined joint force will interact with NATO.

Detailed planning of the Combined Joint Force (CJF), evolving from the currently existing Combined Joint Expeditionary Force (CJEF), is currently under way with French colleagues following the UK-France declaration announcement. This will be done in full consultation with NATO with respect to the Allied Rapid Reaction Corps (ARRC).

As stated in the declaration the CJF will ensure the ability to plan and command a Combined Corps Capability. This corps can provide the Land component of a broader joint force combining all military functions, as part of NATO or bilaterally. The force will draw on corps level capabilities, including elements of the ARRC, as forces currently do under the CJEF Concept of Employment. It is not intended that the CJF will replace the ARRC, rather it will strengthen our warfighting corps through a deepened framework for interoperability and training.

As this will be a NATO Strategic Reserve Corps, it is anticipated that the forces held at readiness for NATO will include those held at readiness for the CJF. The CJF will be fully interoperable and able to act in lockstep with the Alliance, whilst also providing a resilient framework for bilateral operations. The CJF will complement our already significant contribution to the Alliance.

The current structure of the CJEF under its Concept of Employment (CONEMP) is for the use of high readiness national forces to respond to a crisis situation. There is no specified CJEF ‘state of readiness’. UK Troops offered to NATO as part of the Strategic Reserve Corps are currently held at Tier 3 with a readiness of 31-180 days.

The current command structure of the CJEF, under its Concept of Employment (CONEMP), does not discriminate between using those forces already held at readiness for NATO or otherwise.