Iran is reducing its enriched uranium nuclear stockpile as required by its  landmark deal with world powers , but much work remains to be done to resolve all concerns about Tehran’s activities, the United Nations atomic watchdog chief, Yukiya Amano , said Monday. Among measures Iran is taking since the  interim agreement took effect on Jan. 20  is the dilution of its stock of higher-enriched uranium to a fissile concentration less suitable for any attempt to fuel an atomic bomb. Amano, director general of the International Atomic Energy Agency (IAEA), indicated that Iran had made sufficient progress in this regard to receive a scheduled March 1 installment of $450 million out of a total of $4.2 billion in previously blocked overseas funds. The IAEA has a  pivotal role  in checking that Iran is living up to its part of the six-month accord in curbing its disputed nuclear program in […]