US sources announced that despite the unilateral sanctions imposed by Washington against Tehran, Iran is close to completing purchases of 220,000 tons of wheat from American exporters due to be shipped as early as April. The US said Iran has purchased 60,000 tons of American wheat, reopening grain trade ties between the two countries amid Washington\'s tough sanctions against the Islamic Republic. According to a Reuters report published on Friday, it is the first time in three years that Iran has purchased US wheat. The industry sources said Iran was close to completing purchases of another 220,000 tons to be shipped as early as April, and in talks with exporters to buy another undisclosed amount. The price tag for the 400,000 tons of grain - 180,000 confirmed and 220,000 yet to be formally declared - could be around USD 160 million, export sources said. Trade sources said grain giants Cargill Inc. and Bunge Ltd were the likely suppliers to Iran. The two companies were also major sellers of wheat to Iran three years ago when Iran, normally self-sufficient in wheat, bought nearly 7 million tons on the world market, including 1.8 million tons from the United States. Iran has purchased some 2 million tons of wheat from several origins since February in an effort to build its food stockpiles. Many US enterprises complain that Washington\'s wrong policies have cost them the Iranian market which could, otherwise, bring them billions of dollars in trade. Hence, a large number of the US companies and firms have started business activities in or with Iran despite the opposition of the White House leaders. In December 2010, the New York Times reported that over the past decade, United States-based companies have done billions of dollars in trade with Iran despite sanctions and trade embargoes imposed on Tehran. One American company, the daily said, was permitted to do work on an Iranian gas pipeline, despite sanctions aimed at Iran\'s gas industry in particular. The transactions have been made possible by a 2000 law that allows exemptions from sanctions for companies selling food or medical products, the report added. Iranian officials have always stressed that the international and unilateral sanctions against Iran have had no result but inflicting damage on the western companies.