<Tr> <Td> </Td> <Td> Statement on the Panama Canal treaty signing Play media Jimmy Carter's speech upon signing the Panama Canal treaty, September 7, 1977 Statement on the Panama Canal treaty signing Audio - only version </Td> </Tr> <Tr> <Td_colspan="2"> Problems playing these files? See media help . </Td> </Tr> <P> After construction, the canal and the Canal Zone surrounding it were administered by the United States . On September 7, 1977, US President Jimmy Carter signed the Torrijos - Carter Treaty setting in motion the process of transferring control of the canal to Panama . The treaty became effective on October 1, 1979, providing for a 20 - year period in which Panama would have increasing responsibility for canal operations before complete US withdrawal on December 31, 1999 . Since then, the canal has been administered by the Panama Canal Authority (Autoridad de Canal de Panama, or ACP). </P> <P> The treaty was controversial in the US, and its passage was difficult . The controversy was largely generated by contracts to manage two ports, at either end of the canal, which were awarded by Panama to Hong Kong - based conglomerate Hutchison Whampoa . According to US Republicans, the company has close ties to the Chinese government and the Chinese military . However, the United States Department of State said that it found no evidence of connections between Hutchison Whampoa and Beijing . Some Americans were wary of placing the strategic waterway under the protection of Panamanian security forces . </P>

When was the panama canal returned to panama
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