Hay–Bunau-Varilla Treaty, (Nov. 18, 1903), agreement between the United States and Panama granting exclusive canal rights to the United States across the Isthmus of Panama in exchange for financial reimbursement and guarantees of protection to the newly established republic. The United States had offered similar terms to Colombia, which then controlled Panama, in the Hay–Herrán Treaty (Jan. 22, 1903), but they were rejected by the Colombian government as an infringement on its national sovereignty and because it considered the compensation inadequate.
With the tacit approval of the U.S. government and the benevolent presence of the U.S. Navy in nearby waters, Panama declared its independence of Colombia on November 3, followed by de facto U.S. recognition three days later. On the 18th, Philippe Bunau-Varilla, representing Panama, met with Secretary of State John M. Hay in Washington, D.C., to negotiate the treaty that gave the United States in perpetuity a strip 10 miles (16 km) wide across the isthmus for canal construction. The United States was allowed to govern and fortify this Canal Zone. In return Panama was guaranteed its independence and received $10,000,000 outright plus an annuity of $250,000 beginning nine years later. The treaty was ratified by both countries in 1904, and the Panama Canal was completed in 1914.
From its inception, there were intermittent disputes over interpretation of the treaty and charges of U.S. discrimination against Panamanians in the zone. In 1978 two new treaties were concluded detailing the steps by which the United States would transfer to Panama full control over the zone and the canal in the year 2000.