The U.S. Constitution says in Article II, Section II, Clause II that the president "shall have power, by and with the advice and consent of the Senate, to make treaties, provided two thirds of the Senators present concur..." The U.S. Senate is thus vital in the treaty-making process.
This category covers present and proposed treaties and other international agreements. It does not cover historical treaties, treaty controversies, and treaty ratifications, which are covered elsewhere.
International treaties must be approved by two-thirds of the Senate according to Article II, Section II, Clause II of the U.S. Constitution. However, other international agreements do not require approval by a supermajority of the Senate.