The General Authority for Supply Commodities (GASC) has signed a contract to buy 175,000 tons of wheat from Romania, Russia and the United States during the period between April 10 and 20.The deal includes 60,000 tons from Romania, 60,000 tons from Russia and 55,000 from the US at an average price of 312 US dollars per ton, authority's deputy head Mamdouh Abdel Fattah said.