By the powers given in the Constitution, the president may veto bills passed by Congress. In turn, Congress may override a presidential veto. To do so, there must be a two-thirds vote in both the Senate and the House of Representatives.
The United States Congress is one of the three branches of government and is known as the legislative branch. It is the only part of the government allowed to make new laws or change any existing laws. Article I of the Constitution specifies the powers of Congress.Learn more about Branches of Government