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Deploying the armed forces in the UK

The armed forces can be deployed in the UK to assist with the response to crises or major events.

This may be to assist with natural disasters such as flood relief or wildfires, providing niche capabilities such as bomb disposal or to support major national events such as the Olympic or Commonwealth Games.

Such requests are known as military aid to the civil authorities, or MACA.

The armed forces do not maintain specific forces to assist civil authorities, as assistance is provided depending on the requirement. ­­­­­­

Military leaders and senior politicians are concerned that the military is being relied upon too often for this kind of assistance, to the detriment of its own tasks.

This briefing forms part of a series of Commons Library papers on defence readiness, civil preparedness and resilience ahead of expected defence legislation later in the parliamentary session.

Defending the UK against military threats is distinct to MACA and is not the subject of this briefing paper.

When can the armed forces be deployed in the UK?

Civil authorities, such as the emergency services or local authorities, take the lead in responding to any emergencies or non-military threats to the safety and security of the UK and its citizens.

Government departments or civil authorities may call upon the armed forces to assist in planning for, or the response to, an emergency. This is known as Military Aid to the Civil Authorities (MACA).

Ministerial approval is required except when life is immediately at risk.

Guidance on the nature, planning, command and control and conduct of military aid to the civil authorities and military operations is set out in Joint Defence Publication UK Operations: The Defence contribution to resilience (Joint Doctrine Publication (JDP) 02).

What sort of things can the armed forces do under MACA?

The armed forces may be called upon by local and civil authorities for a wide range of tasks. But broadly speaking the military may be called upon in an emergency:

• for their niche capabilities, such as bomb disposal
• general support when civil authorities’ capacity/capability is overwhelmed by an incident
• in preparation for major national events

Bomb disposal

One of the most common tasks provided by the armed forces is explosive ordnance disposal.

The Ministry of Defence (MOD) has a long-standing agreement with the Home Office to respond to and make safe chemical, biological, radiological, nuclear and explosive devices in the UK. This is known as Operation Tapestry. Specialist units operate “in support of, and under the direction of, the civil police throughout the UK”. The armed forces responded to 2,268 call outs under Operation Tapestry in financial year 2025/26.

Natural disasters and extreme weather emergencies

One of the most visible uses of the armed forces on MACA operations is when they are called upon to provide support to responses to natural disasters such as flood relief.

The Department Environment, Food and Rural Affairs has longstanding arrangements with the MOD to secure military support for flood response when required; the armed forces provided support in response to flooding from heavy rainfall in Cumbria in 2015, Lincolnshire in 2019 and West Yorkshire in 2020. 

Section 8 of this briefing asks whether the effects of climate change could result in increased demand for the armed forces in the UK.

Supporting major events

Personnel have been called upon to protect major events, such as G8 or NATO summits. 18,000 military personnel were involved in protecting the 2012 Olympic Games.

Around 1,000 personnel supported the 2022 Commonwealth Games in Birmingham, either in support of the West Midlands police security operation or involved in ceremonial duties or civil engagement.

Industrial action

Personnel may be trained in anticipation of industrial action by emergency or essential services. The MOD made available 248 military fuel tanker drivers during a national shortage in HGV drivers in 2021.

Covid 19 pandemic response

Armed forces personnel were used throughout the covid 19 pandemic in a variety of ways, including supporting the roll-out of testing facilities and vaccine provision. Approximately 34,000 personnel were deployed on 466 MACA tasks during the covid 19 pandemic (for the period 17 March 2020 and 1 April 2022). A regional breakdown is available in a parliamentary written answer (June 2022).

Aerial reconnaissance

An example of a niche capability is the ability of the armed forces to provide specialist aerial imagery. In the winter of 2013 to 2014, the RAF (Royal Air Force) used reconnaissance air capabilities to help provide imagery of flooding along the River Thames to assist with the overall flood relief operation.

The RAF no longer provides a search and rescue capability; this ended in 2015.

Terror attacks

Military personnel can provide support to the police in response to terror threats or attacks.

In February 2003, troops in armoured personnel carriers were deployed to Heathrow airport in February 2003 as part of a temporary tightening of security in the capital. The Ministry of Defence provided logistical and technical support after the 7/7 bombings in 2005.

Operation Temperer is the name of the operational contingency plan to support the police following a terror attack. The Home Office has published a factsheet with frequently asked questions about Operation Temperer.

Countering drones

Countering drones, or uncrewed air systems (UAS), is the responsibility of the Home Office. However, the Ministry of Defence has provided counter-UAS assistance to police forces on a number of occasions in recent years: 13 times between 2022 and September 2025.

The RAF Regiment has a dedicated specialist unit for this purpose: 2 C-UAS Wing. The MOD has said the unit has provided counter-drone security to “high-level Royal and political engagements, major public events, and can respond to suspected drone incursions across the UK”.

Support planning

The Ministry of Defence is not a designated lead department for planning for, and responding to, any civil contingencies, except in the event of a defence nuclear material accident or emergency.

However, the Ministry of Defence’s role in helping other government departments prepare for potential emergencies has become more formalised; the 2015 Strategic Defence and Security Review announced military planners were to be placed in key government departments to give the military a “wider and more formal role in supporting national resilience contingency planning”.

Are there specific units to assist civil authorities?

The armed forces do not maintain specific forces to assist civil authorities, as assistance is provided depending on the requirement.

However, some units are maintained at high readiness to respond to emergencies in the UK.

As well as the RAF’s counter-drones and the specialist explosive ordnance disposal units mentioned above, the Army maintains three UK Standby Battalions at extremely high readiness to respond to emergencies in the UK. These army units amount to 900 service personnel on 24 to 48 hours’ notice to move.

Do soldiers carry their weapons?

Very rarely. Explicit authorisation is required for personnel to be armed.

The MoD’s guidance states “using military personnel armed with weapons for MACA operations will always be an exception”.

Can soldiers arrest people?

Responsibility for law enforcement lies with the police and the Home Office. The MOD guidance is clear that all MACA operations must be conducted within the law. Unlike the police, service personnel only have the same powers of arrest as ordinary citizens. The MOD’s guidance document states this “may limit the breadth of their utility when supporting the police”.

There was some discussion during the Brexit process about deploying the military to help maintain public order. The MoD said in September 2019: “the maintenance of public order is the responsibility of the police. There are no plans to utilise military personnel in the event of civil unrest in the event of a no-deal Brexit”.

Ministry of Defence Police powers

The Ministry of Defence has a specialist, national civilian police force, the Ministry of Defence Police (MDP), whose officers have the full powers and privileges of constables, identical to other civil police officers in the UK, within the jurisdiction defined by the MOD Police Act 1987. That jurisdiction is limited and largely confined to areas they protect, such as military sites, nuclear facilities and relevant government buildings. MDP officers are authorised to carry weapons.

The Anti-Terrorism, Crime and Security Act 2001 allows MDP officers to exercise police powers where a local police force requests the assistance of MDP officers. On those occasions, MDP police will be under the operational control of the local Chief Constable from the requesting force, and will have the same police powers as officers of that force. Further information on MDP jurisdiction and policing protocols with other forces is available on gov.uk: MDP jurisdiction.

How often is MACA used?

The armed forces can be called out dozens of times a year to provide military aid to the civil authorities.

The MOD publishes the number of operations, or tasks, conducted under MACA in each financial year in its MOD annual report and accounts publications (see table 1).

The MOD has said it is “not standard practice” to publish MACA requests. Nor does it routinely record the number of requests made which are not approved.

Significant numbers of personnel were deployed on MACA tasks during covid 19 (2020 to 2022), the Queen’s funeral (2022) and the King’s Coronation (2023).

Are the armed forces being used “more often”?

The Ministry of Defence says the military aid to the civil authorities process means that “when civil authorities cannot manage a disruptive incident and all other options are exhausted, we can deploy our unique capabilities to assist”.

However, concerns about MACA demands have been raised.

In a debate in April 2026 about potentially activating the national emergency plan for fuel, Lord Lancaster of Kimbolton (non-affiliated), director of the Army Reserve and a former Defence Minister, said the use of the military has become the “default setting for many government departments”.

The House of Commons Defence Select Committee had raised such concerns in a report published in 2022:

[…] We are seeing Defence being used more and more often as an emergency measure to relieve exceptional pressures on public services and perform such tasks that otherwise might be expected to be carried out by others.

The government responded the committee’s concerns in its response to the report, setting out the arrangements under which the armed forces may, and may not, be called upon under the MACA process:

The Ministry of Defence would not sanction arrangements where the military are fulfilling civilian tasks, unless other solutions have been exhausted beforehand.

Personnel have reported to be feeling the strain of MACA operations. In a report published in 2022, The Armed Forces Pay Review Body reported personnel felt the “the armed forces had been asked to help support a government response to one event after the other”.

Impact on regular tasks

There are also concerns that using the armed forces for MACA tasks might negatively affect their ability to fulfil their everyday tasks.

James Heapey, then Minister for the Armed Forces, said that during the early stages of the pandemic “a number of lower priority Defence tasks were paused or halted” to allow for the establishment of the covid support force.

During discussions about potentially using armed forces personnel to provide strike cover in 2022, the then Chief of the Defence Staff, Admiral Sir Tony Radakin, said the armed forces are not “spare capacity” and have to be able to “focus on our primary role”.

Could the effect of climate change increase demand on the armed forces?

There is long-standing provision for civil authorities to call upon the armed forces for assistance when responding to adverse weather events.

In 2020, the Ministry of Defence published an external report examining the implications of climate change for the UK armed forces. The report warned that an increase in MACA operations "can be expected in response to climate change". Such demands would have "implications for force planning and the balance of national and international Armed Forces commitments".

A former senior army officer, Lieutenant General Richard Nugee, who previously led on climate change and sustainability at the Ministry of Defence, has said “we're seeing a growing need for military support in emergencies: floods, fires, heatwaves” when discussing the implications of climate change on national security.

Wildfires during the heatwaves in England and Wales in summer 2026 prompted calls for support from the military to tackle wildfires, although there were concerns that the RAF’s two helicopters equipped to deal with wildfires were unavailable because they are regularly based in Cyprus during summer months.

Who pays for MACA operations?

With a few exceptions, MACA activity is not funded from the defence budget. This means the MOD can recover costs involved from the requesting government department or civil authority. The Treasury’s guidance on spending in a crisis sets out this principle:

Managing Public Money requires that government departments must charge for services that do not form part of their funded tasks and that departments must not profit from activity carried out on behalf of another department. With a few exceptions, MACA activity is not funded within the MOD budget and is conducted on a repayment basis.

The charging policy is set out chapter 2, section 4 and annex 2A of JDP 02:UK Operations: The Defence Contribution to Resilience, which was published in 2021. However, an update on the gov.uk website says that, as of 15 March 2024, these section are now out of date, and will be updated at the next review of the publication.¹ Readers are guided to a Joint Service Publication (JSP 462) which sets out financial management in the MOD, but the latest version of this publication is not accessible to the public.

What is the legal basis for MACA?

The legal authority to use Service personnel in operations under Military Aid to the Civil Authorities (MACA) is governed by the Civil Contingencies Act 2004 and the Emergency Powers Act 1964 (Section 2). In addition, service personnel can deploy under the Royal Prerogative for military tasks.

In July 2026, the government launched a Call for Views on the upcoming review of the Civil Contingencies Act and associated regulations, which is due in 2027.

Authorisation process

With only a few exceptions, requests for military assistance must be approved by the Ministry of Defence. In certain cases – when there is an urgent need to protect life, alleviate distress and/or protect significant property – local commanders are empowered to respond under the authority of a 1983 Standing Defence Council Order.

Guidance on the nature, planning, command and control and conduct of military aid to the civil authorities and military operations is set out in Joint Defence Publication UK Operations: The Defence contribution to resilience (JDP 02).

Maca principles

According to the MOD’s guidance, MACA may be provided where:

• there is a definite need to act and the tasks the Armed Forces are being asked to perform are clear;
• other options, including mutual aid, commercial alternatives and the voluntary sector have been discounted;
• the civil authority lacks the necessary capability to fulfil the task and it is unreasonable or prohibitively expensive to expect it to develop one; or the civil authority has all or some capability, but it may not be available immediately, or to the required scale, and the urgency of the task requires rapid external support from the MOD.

A new Defence Readiness Bill?

The government has confirmed plans to introduce legislation later in this Parliament to ensure that the government has the necessary powers to respond to “the growing threat posed by sub-threshold and hybrid attacks” and that it will provide a framework of reserve powers that can be “activated, if required”, to support an effective response during a national crisis and in the event of escalation towards conflict.

This reflects a recommendation in the 2025 Strategic Defence Review (SDR) for a Defence Readiness Bill. The SDR also said it welcomed Cabinet Office proposals to “codify ‘civilian assistance to military authorities’ in crisis and conflict” as part of its work on the Home Defence Programme (see below).

What is the Home Defence Programme?

In 2024 the Cabinet Office established its Home Defence Programme to build the UK’s resilience in the event of any crisis and potential escalation to conflict. Described as “an evolving and enduring programme of work which provides defence, security and resilience planning” it is focused on bringing together military and civilian efforts in the event of a crisis or hostilities affecting the UK.

One benefit of this would be to enable the armed forces to focus on their core military tasks in the event of a crisis, rather than being asked to fulfil MACA tasks.

A new reserve-style force to protect critical national infrastructure?

A “key component” of the Home Defence Programme is developing plans for civilian assistance to the military in a time of conflict. The SDR suggested the government explore options to develop a new 'Home Guard' style force, modelled on the Reserves, that could protect key critical national infrastructure, to ensure the protection of energy, food, water, telecoms, medical supplies and transport infrastructure in the event of crisis or conflict.

The SDR suggested that the creation of such a force would increase “resilience and strategic depth by ensuring Regulars and Reserves can concentrate on warfighting, not basic tasks”.

Further detail on proposals for a new home defence force is available in Commons Library briefing Home defence: A new home guard?