 The Library of Congress Country Study for the Congo says at this point that : " [ On 5 September 1960 ] Kasavubu also appointed Mobutu as head of the ANC . Joseph Ileo was chosen as the new prime minister and began trying to form a new government . Lumumba and his cabinet responded by accusing Kasa @-@ Vubu of high treason and voted to dismiss him . Parliament refused to confirm the dismissal of either Lumumba or Kasavubu and sought to bring about a reconciliation between them . After a week 's deadlock , Mobutu announced on September 14 that he was assuming power until December 31 , 1960 , in order to " neutralize " both Kasavubu and Lumumba . " 
