who must approve treaties made by the president
Treaty Clause The Treaty Clause is part of Article II, Section 2, Clause 2, of the United States Constitution, that empowers the President of the United States to propose and chiefly negotiate agreements between the United States and other countries, which, upon receiving the advice and consent of a two-thirds supermajority vote of the United States Senate, become treaties under international law.
Advice and consent In the United States, "advice and consent" is a power of the United States Senate to be consulted on and approve treaties signed and appointments made by the President of the United States to public positions, including Cabinet secretaries, federal judges, United States Attorneys, and ambassadors. This power is also held by several state Senates, which are consulted on and approve various appointments made by the state's chief executive, such as some statewide officials, state departmental heads in the Governor's cabinet, and state judges (in some states).