The Foreign Sovereign Immunities Act (28 U.S.C. Sec. 1608(a)(1)-(4)) (FSIA) prescribes the mandatory means of service for suits against a foreign State, state agency or instrumentality of a foreign state. Once we are provided the necessary information:
The FSIA provides for service of process on foreign state defendants based upon their definition under §1603. Based upon this definition, the methods of service are mandated under a hierarchical system:
The FSIA also clarifies the circumstances in which a foreign state, political subdivision, agency or instrumentality of a foreign state, might be immune from suit and dictates that service of process must be effected in compliance with the provisions of the Act as stated within 28 U.S.C. §l608.
The final option for FSIA service, via diplomatic channels, provides for service through diplomatic channels if service could not be made under the first two options, or within 30 days by mail from the forum U.S. court clerk. Service cannot be requested via diplomatic channels if the previous methods for service are applicable and have not been exhausted.
It must be kept in mind that if a country which is a signatory to the Hague Service Convention has declared a formal objection to service by mail, the option of service by mail cannot be attempted.