dubai iran confirm sunday appeal court uphold 10-year jail term u.s. citizen two iranian-americans u.s. resident lebanon convict spy charge july u.s. president donald trump warn iran would face new serious consequences unless unjustly detain american citizens release return tehran prosecutor abbas jafari dolatabadi identify four princeton university student xiyue wang iranian-american businessman siamak namazi elderly father baquer nizar zakka lebanese citizen permanent u.s. residency judiciary official news website report washington jar genser lawyer namazis say statement carry u.s. media last week family inform tehran court uphold convictions days early early august princeton university wife wang history doctoral student u.s. citizen say inform iranian authorities deny appeal wang conduct dissertation research iran 2016 detain charge spy cover research accusation family university deny iran sentence zakka lebanese citizen permanent u.s. residency 10 years prison 4.2 million fine 2016 find guilty collaborate state accord u.s.-based lawyer zakka information technology expert invite iran government official year early disappear attend conference tehran iran 2015 nuclear deal world power lift international sanction promise iran reintegration global community exchange curb nuclear programme potential detente west alarm iranian hardliners see flood european trade investment delegations arrive tehran discuss possible deal accord iran experts security officials arrest dozens artists journalists businessmen include iranians hold joint american european canadian citizenship part crackdown western infiltration arrest undermine president hassan rouhani goals revive business political tie west well push political social reform home iran experts observers say number iranian dual nationals unite state britain austria canada france detain past year keep behind bar charge include espionage collaborate hostile governments accord former prisoners families current ones diplomats case detainees keep use prisoner exchange western countries january 2016 unite state iran reach historic prisoner swap deal saw iranians hold charge unite state mostly sanction violations release return americans imprison iran iran say jail u.s. student dual nationals lose spy appeal