johannesburg fbi open investigation u.s. link south africa guptas escalate scandal family allege use friendship president jacob zuma control state businesses financial time say thursday separately britain bank regulator financial conduct authority fca say contact two uk bank possible link gupta family guptas zuma deny wrongdoing gupta family spokesman gary naidoo could reach comment u.s. embassy pretoria immediate comment family founder business empire span media mine consult name trove leak email allege graft deal south africa state-owned company also name several global firm financial time cite people familiar matter say u.s. investigators look individuals bank account company u.s. tie allege graft involve family give detail britain fca say contact hsbc standard charter bank follow report british newspapers finance minister ask regulators investigate lenders possible tie gupta family zuma fca already contact bank name consider carefully responses receive regulator say standard charter london say able comment detail client transactions add internal investigation account close us early 2014 hsbc say comment matter britain parliament expect discuss british bank possible involvement gupta case thursday zweli mkhize one several potential candidates replace zuma head african national congress december say unite state britain within right investigate information suggest corruption irregularities need investigate across border restrict south africa tell reporters guptas company charge crime south africa scandal one many dog zuma presidency local media report extensively so-called gupta-leaks thousands email guptas lieutenants state-owned company politically connect individuals private sector firm fbi open investigation south africa 's guptas ft