According to the preamble to contract law, treaties are a source of international law. If an act or absence is condemned by international law, the law will not accept its international legality, even if it is authorized by domestic law.  This means that in the event of a conflict with domestic law, international law will always prevail.  Prior to 1871, the U.S. government regularly entered into contracts with Indians, but the Indian Appropriations Act of March 3, 1871 (Chapter 120, 16 Stat. 563) had annexed a horseman (25.C No. 71) who effectively terminated the presidential treaty by presenting that no Indian nation or tribe can be recognized as a nation, tribe or independent power – with which the United States can enter into contractual contracts. After 1871, the federal government continued to maintain similar contractual relations with Indian tribes through agreements, statutes and executive ordinances.  A treaty is an international agreement between sovereign states (countries) and, in some cases, international organizations, which is binding under international law. An agreement between an Australian state or territory and a foreign government will not be a treaty.
An agreement between two or more states will not be a treaty unless those countries consider making it binding under international law. Australian contracts are generally covered by the following categories: delivery, postal agreements and fund orders, trade and international conventions. In international law and international relations, a protocol is usually an international treaty or agreement that complements an earlier treaty or international agreement. A protocol may modify the previous contract or add additional provisions. The parties to the previous agreement are not required to adopt the protocol. This sometimes becomes more evident by calling it an “optional protocol,” especially if many parties to the first agreement do not support the protocol. Australia`s Constitution allows the executive government to enter into contracts, but it is customary for contracts to be presented in both houses of Parliament at least 15 days before signing. Treaties are considered a source of Australian law, but sometimes require the adoption of a parliamentary act based on their nature. Contracts are managed and maintained by the Department of Foreign Affairs and Trade, which stated that the “general position under Australian law is that contracts to which Australia has joined, with the exception of those that end a state of war, are not directly and automatically included in Australian law. Signing and ratification do not allow treaties to operate on national territory.