BEIJING -- The trade volume in China's cross-border e-commerce pilot cities surpassed 3 billion yuan (488.73 million) by the end of 2014, official data showed Monday.

E-commerce exports accumulated 2.04 billion yuan across 16 pilot cities, including Shanghai and Beijing, in the 18 months since July 2013, while imports totaled 1.01 billion yuan in six cities, the General Administration of Customs (GAC) data showed.

GAC started its cross-border pilots in 2012 to promote better supervision for the emerging sector.

GAC spokesperson Zhang Guangzhi said the authority was promoting a national unified system for e-commerce trading clearance to improve efficiency and cut costs.