The details of the arrangements for U.S. operation and defense of the Canal under the Panama Canal Treaty are spelled out in separate implementing agreements. The Canal Zone and its government ceased to exist when the treaties entered into force and Panama assumed jurisdiction over Canal Zone territories and functions, a process which was finalized on December 31, 1999. | The details of the arrangements for U.S. operation and defense of the Canal under the Panama Canal Treaty are spelled out in separate implementing agreements. The Canal Zone and its government ceased to exist when the treaties entered into force and Panama assumed jurisdiction over Canal Zone territories and functions, a process which was finalized on December 31, 1999. |