istanbul/ankara turkey cast testimony wealthy gold trader u.s. court attempt undermine ankara economy friday highlight president tayyip erdogan may use politically charge case rally nationalist support trader reza zarrab tell new york court wednesday erdogan authorize transaction scheme help iran evade u.s. sanction dual national iran turkey zarrab cooperate u.s. prosecutors trial turkish bank executive accuse help iran launder money executive plead guilty court case stop judicial become completely political sole aim corner turkey economy prime minister binali yildirim say case aggravate tension ankara washington nato ally already odds syria policy unite state failure extradite muslim cleric turkey accuse engineer fail military coup last year although economic fall-out case could substantial especially u.s. authorities fine turkish bank analysts say erdogan unlikely damage politically home could potentially emerge strong attract nationalist support bolster claim fight independence battle foreign enemies say halil karaveli editor turkey analyst policy journal go political impact suspect actually help electoral sense media coverage case limit turkey one pro-government outlet brand trial conspiracy enemies country erdogan govern turkey almost 15 years yet respond courtroom claim already dismiss case politically inspire attempt bring turkish government government say network u.s.-based cleric fethullah gulen blame ankara fail military coup also behind court case zarrab deposition u.s. court impact outlook ak party constituency return mitigate possible economic impact challenge especially turkish bank eventually fin say sinan ulgen analyst former turkish diplomat international investors grow nervous turkey tie unite state worsen help drive lira currency 10 percent dollar past three months series record low u.s. legal action allege iran sanction bust risk country bank might suck case lie heart late investor concern u.s. prosecutors charge executive turkey state-owned halkbank mehmet hakan atilla help iran launder money halkbank like atilla say guilty charge testimony zarrab also say turkish officials authorize two turkish bank ziraat bank vakifbank move fund iran ziraat vakifbank deny take part scheme nonetheless investors worry possibility turkish bank could fin fine outsize turkish government want pay allow bank pay turn political standoff great bank sovereign spread say greg saichin head emerge debt allianz global investors london whole issue weigh heavily turkey country allocate capital turkey cast zarrab case attempt undermine politics economy