The board of Hyundai Securities Co. on Thursday approved a deal to allow US investors to acquire a major stake in the financial unit of the embattled Hyundai group, a company official said. A US consortium led by American International Group (AIG) would be allowed to buy the Korean company's preferred shares with voting rights, said the Hyundai securities official. Hyundai securities, one of troubled Hyundai group's three financial units that the US consortium hopes to buy, refused to disclose details. However, the total AIG investment is reported to be worth more than one trillion won. Bureau Report