United Kingdom of Great Britain and Northern Ireland
Practice Relating to Rule 1. The Principle of Distinction between Civilians and Combatants
The UK Military Manual (1958) refers to “the division of the population of a belligerent State into two classes, namely, the armed forces and the peaceful population”.
The UK LOAC Manual (2004) states:
Since military operations are to be conducted only against the enemy’s armed forces and military objectives, there must be a clear distinction between the armed forces and civilians, or between combatants and non-combatants, and between objects that might legitimately be attacked and those that are protected from attack. The principle of distinction, sometimes referred to as the principle of discrimination or identification, separates combatants from non-combatants and legitimate military targets from civilian objects.
In its chapter on air operations, the manual provides: “Parties to the conflict shall at all times distinguish between civilians or other protected persons and combatants and between civilian or exempt objects and military objectives.”
With regard to internal armed conflict, the manual states: “A distinction is to be drawn between those who are taking a direct part in hostilities, who may be attacked, and those who are not taking a direct part in hostilities, who are protected from attack.”
The UK LOAC Manual (2004), as amended in 2010, states:
Since military operations are to be conducted only against the enemy’s armed forces and military objectives, there must be a clear distinction between the armed forces and civilians, or between combatants and non-combatants, and between objects that might legitimately be attacked and those that are protected from attack.
In its written statement submitted to the ICJ in the
Nuclear Weapons case in 1995, the United Kingdom stated: “The parties to an armed conflict are required to discriminate between civilians and civilian objects on the one hand and combatants and military objectives on the other and to direct their attacks only against the latter.”
In 2003, in reply to a written question in the House of Commons, the UK Minister of State for the Armed Forces, Ministry of Defence, wrote: “Cluster bombs have been used against targets for which they were the most appropriate available weapon and where they could be used in accordance with international law, including with the principles of proportionality and discrimination.”
In 2003, in reply to a written question in the House of Commons asking whether he would “make it his policy not to use cluster bombs in urban or populated areas in Iraq”, the UK Secretary of State for Defence wrote:
Cluster bombs are only used strictly in accordance with international law. This includes the principles of distinction and proportionality as well as precautionary measures to be taken in planning and conducting an attack, as contained in the First Additional Protocol of 1977 to the Geneva Conventions of 1949. The targeting process takes account of these principles in matching the type of weapon used to the target to be attacked. There will be circumstances when it would be considered more appropriate to use other munitions than cluster bombs. These circumstances are more likely to arise in urban or populated areas as cluster bombs engage targets that cover an area.
The UK Government Strategy on the Protection of Civilians in Armed Conflict (2010) states: “IHL requires parties to a conflict to respect and protect civilians. In the conduct of military operations they must distinguish at all times between combatants and civilians”.
The UK Military Manual (1958) states:
The most important powers of resistance possessed by a belligerent … are his armed forces with their military stores and equipment, and his defence installations of all kinds. The means of reducing these powers of resistance [include] killing and disabling enemy combatants.
The UK LOAC Manual (2004), as amended in 2010, states:
The principle of distinction separates those who may be legitimately the subject of direct attack, namely combatants and those who take a direct part in hostilities, from those who may not be so subject.
Upon ratification of the 1977 Additional Protocol I, the United Kingdom stated:
It is the understanding of the United Kingdom that … the first sentence of paragraph 2 [of Article 52] prohibits only such attacks as may be directed against non-military objectives; it does not deal with the question of collateral damage resulting from attacks directed against military objectives.
At the CDDH, the United Kingdom stated that it did not interpret the obligation in the first sentence of Article 47(2) of the draft Additional Protocol I (now Article 52(2))
as dealing with the question of incidental damage caused by attacks directed against military objectives. In its view, the purpose of the first sentence of the paragraph was to prohibit only such attacks as might be directed against non-military objectives.
In 2003, in reply to an oral question in the House of Lords asking “what in the circumstances of the Iraq of today constitutes the enemy”, the UK Parliamentary Under-Secretary of State for Defence stated: “My Lords, the potential enemy are all those, wherever and whoever they are, who seek to engage British forces in a hostile manner.”
The UK Government Strategy on the Protection of Civilians in Armed Conflict (2010) states: “IHL requires parties to a conflict to respect and protect civilians. In the conduct of military operations they must distinguish at all times between combatants and civilians, and only direct attacks against suspected combatants”.
The UK Military Manual (1958) states: “It is a generally recognised rule of international law that civilians must not be made the object of attack directed exclusively against them.”
The UK LOAC Pamphlet (1981) states: “Civilians are protected from attack under the law of armed conflict.”
The UK LOAC Manual (2004) states: “The civilian population as such, as well as individual civilians, shall not be the object of attack.”
In its chapter on air operations, the manual further states: “The civilian population and individual civilians must not be attacked and must be protected against the dangers arising from military operations.”
The UK Geneva Conventions Act (1957), as amended in 1977, punishes “any person, whatever his nationality, who, whether in or outside the United Kingdom, commits, or aids, abets or procures the commission by any other person of, a grave breach of … [the 1977 Additional Protocol I]”.
Under the UK ICC Act (2001), it is a punishable offence to commit a war crime as defined in Article 8(2)(b)(i) and (e)(i) of the 1998 ICC Statute.
In 1938, during a debate in the House of Commons, the UK Prime Minister listed among rules of international law applicable to warfare on land, at sea and from the air the rule: “It is against international law to bomb civilians as such and to make deliberate attacks upon civilian populations.”
At the CDDH, the United Kingdom voted in favour of Article 46 of the draft Additional Protocol I (now Article 51), describing its first three paragraphs as containing a “valuable reaffirmation of existing customary rules of international law designed to protect civilians”.
A training video on IHL produced by the UK Ministry of Defence illustrates the rule that military operations must not be directed against civilians.
In its written statement submitted to the ICJ in the
Nuclear Weapons case in 1995, the United Kingdom stated: “It is a well established principle of customary international law that the civilian population and individual civilians are not a legitimate target in their own right.”
In 2006, in reply to questions in the House of Commons concerning,
inter alia, the treatment of the Karen people in Myanmar, the UK Minister of State for Trade, Foreign and Commonwealth Office, stated: “We condemn the attacks carried out by the Burmese army on civilians in northern and western Karen State.”
In 2007, in a written answer to a question in the House of Lords concerning civilian casualties in Afghanistan, the UK Government Spokesman for the Foreign and Commonwealth Office wrote:
The UK joins the Agency Co-ordinating Body for Afghan Relief in condemning the actions of armed insurgents causing civilian casualties … International forces, including UK forces, seek at all times to avoid loss of civilian life. The targeting process, weapons selection, doctrine, training and rules of engagement are all in line with international humanitarian and human rights law and the law of armed conflict.
In 2009, in response to a question by a Member of the House of Commons, the UK Secretary of State for Foreign and Commonwealth Affairs wrote: “Rocket attacks by Palestinian militants targeted at innocent civilians in southern Israel constitute a breach of international humanitarian law.”
The UK Government Strategy on the Protection of Civilians in Armed Conflict (2010) states:
Protection of civilians in armed conflict matters from a
legal perspective, because the UK has specific obligations concerning the protection of civilians in situations where it is involved in military action. International humanitarian law (IHL) provides that civilians shall enjoy general protection from the effects of armed conflict [and] protects civilians from being the object of attack. … [C]ivilians must not be the target of physical attacks.

[emphasis in original]