SHANGHAI, Feb 17 (Reuters) - China's vice premier Wang Yang said the government will strengthen efforts to rein in a rapid slowdown in the country's imports and exports as soon as possible to prevent the deceleration from turning into prolonged shrinkage, official Xinhua News Agency reported.

China should firmly put to work policies that support international trade, and promote supply-side reforms, Wang was quoted by Xinhua as saying during a trip to eastern Jiangsu province.

Wang said the current situation in the global economy is extremely severe and complicated, putting heavy downward pressure on China's imports and exports, but the fundamentals of China's international trade had not changed, according to Xinhua.

China's January trade performance was worse than expected as tepid demand persisted both at home and abroad, raising expectations of further government measures to arrest the slowdown and to quell market jitters.

January exports fell 11.2 percent from a year earlier - the seventh straight month of decline, while imports tumbled 18.8 percent - the 15th month of decline, both far worse than expected.

(Reporting by Samuel Shen and Engen Tham; Editing by Richard Pullin)