cnn's christiane amanpour. >> i would like to say to american people, i bring peace and friendship from iranians to americans. >> reporter: in an ambitious move -- >> i am directing john kerry -- >> reporter: -- obama publicly directed john kerry to immediately pursue a nuclear agreement with iran though he cautioned the u.s. must know iran is serious. >> to succeed, conciliatory words will have to be matched by actions that are transparent and verifiable. >> reporter: what might the u.s. need to see in any potential deal? the disclosure of all of iran's nuclear sites, a reduction in the number of centrifuges and a cap on uranium enrichment levels