The Committee of Ministers adopts conventions by a two-thirds majority of the vote and by a majority of the principal representations represented on the Committee. Once adopted, the text of the treaty is final. Reserves are essentially reservations about the adoption of a treaty by a state. Reserves are unilateral declarations that purport to exclude or modify the legal obligation and its effects on the booking state.  These must be included at the time of signing or ratification, i.e. “a party cannot add a reserve after having already acceded to a treaty.” Article 19 of the 1969 Vienna Convention on Treaty Law. The only difference between “conventions” and “agreements” is the form by which a state can consent to hiring. Agreements may be signed, with or without reservation, of ratification, acceptance or approval. Conventions can be ratified in principle. See the standard clauses for concluding the agreements and agreements concluded by the Council of Europe. As explained in more detail in 11 FAM 721.2, there are two domestic law procedures by which the United States becomes parties to an international agreement.
First, international agreements (regardless of your title, name or form) that come into force with respect to the United States only take place after two-thirds of the U.S. Senate has given their opinion and approval in accordance with Article II, Section 2, of Clause 2 of the Constitution. Second, international agreements, which come into force with respect to the United States on a different constitutional basis than the Council and Senate approval, are “non-treaty international agreements” and are often referred to as “executive agreements.” There are different types of executive agreements. A treaty is negotiated by a group of countries, either through an organization created for this purpose or by an existing body such as the United Nations Council on Disarmament (UN). The negotiation process can take several years depending on the subject of the treaty and the number of participating countries. At the end of the negotiations, the treaty will be signed by representatives of the governments concerned. Conditions may require that the treaty be ratified and signed before it becomes legally binding. A government ratifies a treaty by tabling a ratification instrument in a treaty-defined location; the ratification instrument is a document containing formal confirmation of the Government`s acceptance of the provisions of the treaty. The ratification process varies according to national laws and constitutions. In the United States, the president can only ratify a treaty after receiving the “consultation and approval” of two-thirds of the Senate. A contract is null and void if it violates a mandatory standard. Unlike other principles of customary law, these standards are not recognized as offences and therefore cannot be changed by contractual obligations.
These are limited to prohibitions as universal as those against the aggressive use of force, genocide and other crimes against humanity, piracy, hostilities against the civilian population, racial discrimination and apartheid, slavery and torture, meaning that no state can legally commit to commit or admit such acts.  Consent is also void if it is motivated by the fraudulent behaviour of another party or by the direct or indirect “corruption” of its representative by another party.