Co-belligerence

Co-belligerence is the waging of a war in cooperation against a common enemy with or without a military alliance. Generally, the term is used for cases where no formal treaty of alliance exists. Likewise, allies may not become co-belligerents in a war if a casus foederis invoking the alliance has not arisen. Co-belligerents are defined in the Encyclopaedic Dictionary of International Law as "states engaged in a conflict with a common enemy, whether in alliance with each other or not".^[1]

^ John P Grant; J.Craig Barker (2 October 2009). Parry and Grant Encyclopaedic Dictionary of International Law. Oxford University Press. p. 102. ISBN 978-0-19-987491-0.

[GrantBarker2009-1] John P Grant; J.Craig Barker (2 October 2009). Parry and Grant Encyclopaedic Dictionary of International Law. Oxford University Press. p. 102. ISBN 978-0-19-987491-0.

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