Government-to-government services exemption excludes GST on intergovernmental supplies, subject to postal, transport and aircraft/vessel exceptions. Services supplied by one government entity to another are exempt from GST, but the exemption excludes services by the Department of Posts and the Ministry of Railways (Indian Railways), services relating to an aircraft or a vessel inside or outside port or airport precincts, and transport of goods or passengers; key terms are defined by reference to the Aircraft Act, Airports Authority of India Act, Major Port Trusts Act and Indian Ports Act.