What law provides the authority for the President to waive the Buy American Statute?

The authority for the President to waive the Buy American Statute is provided under the Trade Agreements Act of 1979. This law allows the President to enter into international trade agreements that can exempt certain procurements from the Buy American requirements. Additionally, the President can also invoke a waiver under the Buy American Act itself in specific circumstances, such as when it is deemed in the public interest or when domestic supplies are not available.