washington u.s. state department say thursday release 400 million cash iran tribunal settlement assure american prisoners free board plane payment 400 million do prisoners release state department spokesman john kirby tell reporters take advantage make sure maximum leverage possible get people get safely kirby add first time administration say publicly use payment leverage ensure prisoners release iran three five prisoners include jason rezaian washington post tehran bureau chief saeed abedini pastor idaho amir hekmati former u.s. marine flint michigan well family members part prisoner exchange follow lift international sanction iran follow nuclear deal 2015. one prisoner nosratollah khosravi-roodsari choose remain iran fifth prisoner american student matthew trevithick release separately u.s. president barack obama secretary state john kerry deny payment ransom release prisoners tie iran nuclear deal white house announce jan. 17 release 400 million fund freeze since 1981 plus 1.3 billion interest owe iran part settlement long-standing iranian claim iran-u.s. claim tribunal hague fund part trust fund iran use 1979 islamic revolution buy u.s. military equipment tie decades litigation tribunal payment make unite state cash due international sanction iran administration maintain negotiations fund prisoners conduct separate track way link representative jason chaffetz chairman house representatives committee oversight government reform ask kerry appear future committee hear discuss payment u.s. say payment iran use leverage prisoners release