China's imports of crude from Iran rebounded to the highest level in six months in December after the United States renewed an exemption from penalties on banks that process payments for the Persian Gulf nation's oil.

China, the world's second-biggest crude consumer, bought 2.52 million metric tons of oil from Iran last month, according to figures released on Monday by the General Administration of Customs. That represents a 43 percent increase from November, when purchases slipped 9.3 percent. Shipments averaged 596,000 barrels a day, the most since June, and advanced 3.6 percent from December 2011, the data showed.