Citigroup Inc said it has been authorized by a U.S. judge to process two Argentine debt payments, the bank said, which could ease tensions between the bank and the default-hit nation. The U.S. bank, which acts as custodian of some Argentine bonds, has been embroiled in a court battle between the South American country and a group of New York-based hedge funds seeking full payment on their defaulted sovereign bonds. A potential resolution may have moved closer after a ruling by the U.S. District Court for the Southern District of New York on Friday.