"A decision on whether to ban imports of oil will be taken tomorrow," the source told RIA Novosti.
Ukraine's sunflower oil exports came under pressure in late April after a 40,000 ton batch was found to contain mineral oil contaminants. This type of oil can cause serious complications if inhaled. Shipments of the contaminated oil from Ukraine have been recalled in Italy, Spain, France, Greece, the Netherlands and the U.K.
Ukrainian authorities have failed to provide guarantees that the oil was safe by a Tuesday deadline, the source said. Kiev claims, however, that the move is aimed at cutting Ukrainian imports to the European market.
A working commission has been set up to investigate the situation. The source of the contamination has not yet been discovered.