## Facts

- In spring 1999, during the Kosovo conflict, NATO member States carried out air strikes against targets in the Federal Republic of Yugoslavia (FRY) (later Serbia and Montenegro).
- Serbia (then FRY) brought proceedings against the Kingdom of Belgium at the International Court of Justice (ICJ), challenging Belgium’s participation in the bombing campaign.
- Serbia alleged that Belgium’s conduct violated international rules on the use of force and related protections owed to another State, including obligations connected to sovereignty and the protection of civilians and property during armed conflict.
- Serbia described the bombings at issue as attacks directed at FRY territory, including strikes described as limited to military objectives such as a military base.
- Serbia requested provisional measures during the 1999 phase of the case, asking the Court to order Belgium to stop and refrain from further acts connected to the NATO air operations while the case was pending.
- Belgium disputed the Court’s jurisdiction at this early stage and opposed provisional measures.
- In the oral proceedings, Belgium argued that its actions were lawful, relying in part on the position that the United Nations Security Council had characterized the situation as threatening international peace and that Serbia’s conduct in Kosovo created a humanitarian catastrophe affecting the Kosovo population.
- Belgium also invoked necessity as a justification, referencing Article 25 of the International Law Commission’s Draft Articles on State Responsibility (as a defense to wrongfulness).
- The 1999 oral proceedings addressed the request for provisional measures and whether the Court had a sufficient jurisdictional basis to act at that stage.

## Issues

1. Whether, at the provisional-measures stage addressed in the 1999 oral proceedings, the ICJ had prima facie jurisdiction over Serbia’s claims against Belgium arising from Belgium’s participation in the NATO air strikes.
2. Whether the conditions for provisional measures were met, including whether the rights claimed by Serbia were plausible and at risk of irreparable prejudice and whether the situation was urgent.
3. Whether Belgium’s asserted justifications (including claimed humanitarian intervention and necessity) affected the Court’s ability to indicate provisional measures at this preliminary stage.

## Decision

- The ICJ declined to indicate provisional measures against Belgium in the 1999 phase.
- The Court concluded that it lacked prima facie jurisdiction, which is required before it can order provisional measures.
- Because prima facie jurisdiction was not shown, the Court did not order Belgium to cease or suspend its participation in the NATO bombing campaign at the provisional-measures stage.
- The Court’s refusal to order provisional measures did not resolve the merits of Serbia’s allegations about the legality of the use of force or Belgium’s asserted defenses.

## Legal Principles

- Provisional measures under Article 41 of the ICJ Statute require a showing that the Court has prima facie jurisdiction; without that threshold showing, the Court cannot grant interim relief.
- At the provisional-measures stage, the Court does not finally decide jurisdiction or the merits; it assesses whether the asserted basis of jurisdiction appears capable of founding jurisdiction and whether interim protection is legally available.
- Assertions about the lawfulness of the respondent’s conduct (including defenses such as necessity or claims of lawful intervention) go to the merits and do not themselves supply jurisdiction where the Court’s jurisdictional basis is uncertain.
- Even where allegations involve serious harm, the Court will not indicate provisional measures unless the jurisdictional precondition is satisfied.

## Conclusion

In the 1999 oral proceedings in *Legality of Use of Force (Serbia and Montenegro v. Belgium)*, Serbia sought provisional measures to halt Belgium’s participation in NATO air strikes, while Belgium contested jurisdiction and argued its conduct was justified, including by necessity and claimed humanitarian considerations; the ICJ ultimately refused to indicate provisional measures because it was not satisfied that it had prima facie jurisdiction at that stage, leaving the underlying legality questions unresolved in the interim order.


Legality of Use of Force (Serbia and Montenegro v. Belgium), Oral Proceedings (1999)