As a rule international organisations have immunities form host state jurisdiction, defined by a constituent treaty or headquarters agreement. Immunity of international organisations is generally founded on the principle of functional necessity: international organisations need immunity to be able to perform their functions independently. The subsequent practice of the organisation and its member states has interpreted this as an absolute immunity from jurisdiction.
However this practice increasingly causes controversy. Claims against international organizations are brought before national courts by those who allegedly suffer from their activities. In a recent Dutch case three fuel supply companies sued NATO’s military headquarters, SHAPE and JFCB, for alleged non-payment in the amount of $217 million under the fuel supply contracts into which NATO entered to logistically support the military operation in Afghanistan.
The court held that NATO‘s immunity from execution can have exceptions deriving from customary international law. The immunity will not apply if the property is specifically in use or intended for use by the IO for other than government non-commercial purposes; the IO has expressly agreed to the taking of enforcement measures; and the property has been designated or reserved for the satisfaction of the claim in question (para. 3.12 – 3.14).
Konstitucijos pr. 7, Vilnius LT-09308