Under the treaty , Panama received , much of which the United States required to be invested in that country , plus annual payments of ; with those payments made , as well as for the purchase of the French company assets , the Canal Zone was formally turned over by Panama on May 4 , 1904 , when American officials reopened the Panama City offices of the canal company and raised the American flag .
While the treaty was approved , the Panamanians received US$ 10 million , much of which the United States required to be invested in that country . The Canal Zone was formally turned over by Panama on May 4 , 1904 , when American officials reopened the Panama City offices of the canal company and raised the American flag .