Rearming the British Army

At the ready: a British soldier holds an anti-tank weapon during an exercise in Estonia in 2017. Image: Defence Imagery / MOD News Licence

The UK is right to arm Ukraine but must replenish its stocks if it is to avoid disarming itself.

British weaponry provided to the Ukrainian Armed Forces has made a material difference on the battlefield. The early provision of the Next-generation Light Anti-tank Weapon (NLAW) prior to the conflict was a valuable demonstration of the UK’s commitment to Ukraine’s survival. Since then, the UK government has been a leading actor in the procurement of Soviet-built munitions and systems for the Ukrainian military and their transfer to Ukraine. But as the UK begins to deliver vitally needed long-range artillery, it is important that other government departments appreciate the need to replenish the UK’s own stocks.

The defence secretary has repeatedly made clear that the war in Ukraine does not demand a fundamental reassessment of the Integrated Review, which accurately identified Russia as the most acute security threat to the UK and prioritised Europe as the primary theatre for deterrence, even as there is a need to compete with China further afield. While the theory behind much of the Integrated Review may hold, however, the translation of theory into practice is being impacted by the war in Ukraine.

The Defence Command Paper – outlining the priorities for British military modernisation – set out some bold bets for the British Army. Headcount was to be reduced to a level that would render the existing UK commitment to NATO and other theatres unsustainable, and armoured infantry were to be removed from the order of battle; all to free up funds to prioritise the acquisition of capabilities that would remain critical through the 2040s – not least fires and the recapitalisation of the UK’s Multiple Launch Rocket Systems (MLRS) and new munition natures.

The loss of armoured infantry represented a fundamental departure from decades of NATO warfighting doctrine. Instead, the British Army was to prioritise liaison and partnered operations in areas of competition, while offering NATO reconnaissance, attack aviation, long-range precision fires, and highly trained infantry to bolster its deterrence posture. Data gathered from Exercise Warfighter and other simulations demonstrated that long-range artillery could have a devastating effect on the enemy if paired with robust reconnaissance and a bearer network to coordinate timely artillery strikes.

It would be foolish for the UK to assume that Russia’s difficulties in Ukraine mean it poses no threat to NATO in the medium term

The Defence Command Paper accepted risk in the short term in exchange for modernisation over the course of the decade, with Boxer and Ajax beginning to enter service from 2023, the mobile fires platform, and Challenger 3 by 2027. In practice, formations would start fielding these capabilities by the end of the decade. At the same time, the force was to take funding marked up for the Multi Role Vehicle-Protected (MRVP) programme and inject it into delivering the next generation of combat systems, with significant experimentation and trials to be conducted early in the 2020s to enable clear bets to be placed in 2025.

This timetable has now gone awry. Ajax is in limbo, with ongoing attempts to mitigate harm to crew preventing trials with the vehicle to assess the impact of vibration on its operational effectiveness. Morpheus – the critical Army network – is also facing delays. UK anti-tank guided missile (ATGM) stockpiles have now been significantly depleted – having been gifted to Ukraine – leaving British units toothless. With the announcement that the UK’s MLRS are also going to be sent to Ukraine, the punch that was supposed to buy out the UK’s lethality in the close fight is about to be stripped from the order of battle. The already woefully inadequate stockpiles of rockets for these systems are now to be expended.

The justification for providing M270 MLRS to Ukraine is sound. Ukraine is attriting the Russian Army and fighting for its survival. Yet it is suffering heavy casualties because it is outranged by Russian artillery in Donbas. MLRS may offer the Ukrainians the capacity to deliver effective counter-battery fire and thereby strip Russia of one of its most lethal advantages on the battlefield.

It would be foolish, however, for the UK to assume that Russia’s difficulties in Ukraine mean it poses no threat to NATO in the medium term. Russia may be defeated in Ukraine. But NATO must ensure that its own deterrence posture is robust by 2027, at which point Russia could realistically have reconstituted many of its units. There is a reason why Finland and Sweden are keen to gain entry to the alliance despite Russia’s poor operational performance. The UK, too – having made commitments to both Scandinavian states prior to their gaining NATO membership – is expanding its defence commitments, even as its actual capabilities diminish. Perhaps most significantly, the US is increasingly pivoting towards China and a change of administration in 2024 could leave deterrence in Europe primarily in European hands.

It is vital that the UK government can show its allies that the British Army will turn up with more than bayonets if Russian aggression should spread beyond Ukraine

In its Spring Statement, the UK government was conspicuous among NATO members by its decision not to increase defence spending. This was justifiable. The Treasury rightly noted that the Ministry of Defence did not have a clear ask at the time and it was too early to tell what priorities would be following the conflict in Ukraine. As the UK empties its stockpiles, however, and as those systems it is not giving to Ukraine see their availability plummet, it is clear that restocking will likely see an immediate need for an injection of funds in the Autumn Statement. Given the lead times required for industry to deliver anything into service, if the UK is to offer NATO any significant capabilities by 2027, orders will need to be made within the next year.

For the British Army, this presents a challenge. Rather than a kneejerk like-for-like replacement of old systems, the intention following the Integrated Review was to place bets on future capabilities. The experimentation to identify which bets to make was supposed to begin this summer. It would, therefore, be unfortunate if the immediate need to replace equipment fixed the Army to capabilities that it does not assess to be critical in the long term.

In order to avoid this, the procurement of new equipment in the autumn should prioritise those capabilities whose long-term utility is beyond doubt. New MLRS and more lethal ammunition natures, raising the pre-Ukraine stocks, appear to be an immediate priority. Accelerating the delivery of the Mobile Fires Platform seems eminently sensible. Bridging and engineering support – currently in a dire state – has had its utility underscored by operations in Ukraine, and is lacking across NATO. Moreover, there is no evidence to suggest the significance of these capabilities will diminish in the future, especially with an increased expectation of urban operations. The UK’s new air defence system, Sky Sabre, is highly capable, and medium-range air defence able to intercept missiles is in short supply across NATO, even as such capabilities have been shown to be critical to Russia’s way of war. Finally, if light infantry is to be at the heart of the British Army – and this appears a certainty – ATGM stocks will need to be not only replenished but increased, along with an uplift in training to ensure units have accredited operators.

The UK government has gained significant credibility among its allies during the war in Ukraine through its willingness to move quickly and decisively in support of its friends. If that credibility is to be translated into influence, however, it is vital that the UK government can show its allies that the British Army will turn up with more than bayonets if Russian aggression should spread beyond Ukraine.

The views expressed in this Commentary are the author’s, and do not represent those of RUSI or any other institution.

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Dr Jack Watling

Senior Research Fellow, Land Warfare

Military Sciences

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