Colombian President Alvaro Uribe has said he did not give any orders to the country's intelligence service to tap phone calls of prominent figures.
Senior officials in the security service, Das, have offered to resign over claims that agents eavesdropped on politicians, judges and journalists.
Mr Uribe blamed the illegal wiretapping on what he called a mafia gang inside the secret service, the Das. He accused them of damaging Colombian democracy and his government.
Mr Uribe said he had never given a single order during his political career to investigate the private lives of his opponents.