Iran\'s decision to halt crude supplies to a number of European states has resulted in a rapid increase in oil prices in the international markets. Brent crude gained 55 cents to $123.15 a barrel on Friday, after falling $2 in the previous session. The US crude also rose 49 cents to $105.60. Oil prices dropped on Thursday following a report that Britain and the United States were preparing to release their strategic oil reserves this year. The report said that Britain had agreed to cooperate with the United States in tapping into its stockpiles in an effort to bring down oil prices, but volumes and exact timelines have yet to be determined. Meanwhile, in the wake of the oil price hikes, gasoline prices shot up in both the United Kingdom and the United States, fueling anger among consumers. Iran\'s Oil Ministry announced on February 19 that it had cut oil sales to British and French firms. Tehran also announced it may also halt oil exports to more European countries. The decision by Iran came after European Union foreign ministers agreed to ban oil imports from Iran and freeze the assets of the Iran\'s Central Bank across the EU in line with a US-led effort to impose further pressure on the Iranian economy over its civilian nuclear program. Meantime, news of Iran cutting supplies to six EU member states caused a lot of concern in Europe and in the world\'s markets. The bloc currently buys about 18% of Iran\'s oil exports. Iran is the world\'s 4th largest oil supplier, with China, Japan, and India its largest buyers.