Rebel forces, particularly Hayat Tahrir al-Sham (HTS) and the Syrian National Army (SNA), carried out an offensive that ended the 50 years of the Assad family's authoritarian rule in Syria. An armed coalition, supported by both state and non-state actors, was involved in this offensive.

The International Humanitarian Law (IHL) classifies two types of armed conflicts: International Armed Conflict (IAC) and Non-international Armed Conflict (NIAC). Common Article 2 of the Geneva Conventions defines international armed conflicts as all instances of declared war or any other armed conflict that may occur between two or more high contracting parties (i.e., States), whether or not one party recognises the state of war. On the other hand, Article 1 of the Additional Protocol II of the Geneva Conventions defines non-international armed conflict as all instances of armed conflict that may occur between state forces and non-state forces or between such non-state forces in the territory of any high contracting party (i.e., State). We cannot simplistically categorise the Syrian conflict as either IAC or NIAC alone as the Syrian conflict simultaneously demonstrates the traits of both IAC and NIAC.

The involvement of a foreign state in a non-international armed conflict presents a significant challenge for IHL in classifying these types of armed conflicts. A non-international armed conflict becomes an international armed conflict when foreign intervention is involved.

Many armed forces were involved in the Syrian conflict, including state and non-state actors. The Assad regime received support from Russia and Iran to fight against many rebel factions. HTS is the Sunni Islamist paramilitary organisation that led the recent offensive and overthrew of Assad. The US-backed Syrian Democratic Forces (SDF) is a Kurdish-dominated coalition of ethnic militias whose military aim is to defeat IS, which controls the northeastern part of Syria. The Free Syrian Army (FSA), a loose umbrella group of armed northern Syrian opposition factions, formed the Syrian National Army (SNA), a Turkish-backed coalition, which collaborated with other rebels, including HTS, to overthrow Assad.

The involvement of a foreign state in a non-international armed conflict presents a significant challenge for IHL in classifying these types of armed conflicts. A non-international armed conflict becomes an international armed conflict when foreign intervention is involved. This requires "overall control" on part of the foreign state as stated by the International Criminal Tribunal for the former Yugoslavia Appeal Chamber in the Prosecutor v Dusko Tadic case. According to the Tadic Appeal Chamber decision, the degree of support, such as military, financial, logistical, political, etc., is required to transform an NIAC into an IAC. The Appeal Chamber further stated that:

"In order to attribute the acts of a military or paramilitary group to a state, it must be proved that the state wields overall control over the group, not only by equipping and financing the group but also by coordinating or helping in the general planning of its military activity. Only then can the State be held internationally accountable for any misconduct of the group. However, it is not necessary that, in addition, the State should also issue, either to the head or to members of the group, instructions for the commission of specific acts contrary to international law."

Therefore, when a foreign state supports a non-state party through military, financial, logistical, political, and other means, we can say that the foreign state has overall control over that non-state armed group, thereby transforming an NIAC into an IAC.

The initial nature of the Syrian conflict was non-international, as it involved the Assad government and certain rebel groups. However, the question remains whether the conflict will remain non-international following the intervention of foreign states that have supported the rebel groups through various means. Iran, Russia, and the Shia Islamist militia Hezbollah backed the Assad regime. Various state parties, including Turkey, Israel, the United States, the Netherlands, and many others, backed the rebel groups. Turkey has played a crucial role as the primary external supporter of the rebel faction since 2011. Turkey has provided arms, military, and political support to rebel factions, the majority of which still operate under the Syrian National Army (SNA) banner. Also, Turkey maintains a military presence in northwest Syria and extends support to certain rebel factions, including the SNA. In addition to providing the groups with the necessary equipment, it seems that Turkey was also actively coordinating and assisting in the planning of their overall military operations. The supply of modern weapons, strategic assistance, and the verifiable increase in military capabilities suggest a further degree of overall coordination. In my opinion, this level of coordination goes beyond the provision of mere material support and transforms the character of the Syrian conflict from NIAC to IAC.

In conclusion, the International Humanitarian Law does not provide any explicit provision for neatly distinguishing a non-international armed conflict (NIAC) from an international armed conflict (IAC). In author's view, factual categorisation classifies situations like the Syrian conflict as international, while a specifically legal categorisation classifies it as non-international.

The writer is final year law student, BRAC university.