The Panama Canal will remain a vital export route for US grains to the Asia-Pacific region after the waterway reverts to Panamanian control in 2000, says Panama's vice-foreign minister. There will be no changes in administration of the canal. 'Japan and China are the second and third-largest customers of the Panama Canal, and their useage is increasing,' Alejandro Ferrer said in Tokyo. 'There will be a smooth transition and no change of administration. The canal will be formally handed over to Panamanian authorities on December 31, 1999.