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. In the absence of legislation, contracts cannot impose obligations on individuals or create rights in national law. Yet international law, including contract law, is a legitimate and important influence on the development of the common law and can be used in the interpretation of laws.  Treaties can be implemented by executive measures and existing laws are often sufficient to ensure compliance with a treaty. Articles 46-53 of the Vienna Convention on Treaty Law define the only ways to declare treaties invalid – which is considered unenforceable and void in international law. A treaty is invalidated either because of the circumstances in which a State party has acceded to the treaty, or because of the very content of the treaty. Cancellation is separate from termination, suspension or termination (addressed above), all of which involve a change in the consent of the parties to a previously valid contract, not the nullity of that consent in the first place. An essential part of treaty drafting is that the signing of a treaty implies recognition, that the other party is a sovereign state and that the agreement, considered to be under international law, is applicable.
Therefore, nations can be very cautious when it comes to qualifying a treaty agreement. In the United States, for example, interstate agreements are pacts and agreements between states and the federal government or between government authorities are statements of intent. Before 1871, the U.S. government regularly entered into contracts with Indians, but the Indians Appropriation Act of March 3, 1871 (Chapter 120, 16 Stat. 563) had a horseman (25 US. C No. 71), which effectively ended the drafting of presidential treaties by declaring that no Indian nation or Indian 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.  In India, the themes are divided into three lists: Union, State and Simultaneous.