(AGI) Moscow, Sept 23 - Gazprom is able to substitute all thematerials imported from Western countries subject to thesanctions imposed on Russia over the Ukrainian crisis, saidvice president of the Russian state gas giant, AlexandrMedvedev, on Tuesday. "We only import 10 percent of ourequipment at Gazprom and the rest is supplied by Russianmanufacturers," Mr Medvedev told an energy sector conference onthe island of Sakhalin. "There is no case (in history) whensanctions have been successful," he added. (AGI) . .