China's exports in yuan-denominated terms surged 18.7 percent year on year in March, while imports dipped 1.7 percent, customs data showed on Wednesday.

That led to a monthly trade surplus of 194.6 billion yuan (29.9 billion U.S. dollars), down from February's 209.5 billion yuan, according to figures from the General Administration of Customs (GAC).

Foreign trade in the first quarter was 5.9 percent lower than a year earlier at 5.2 trillion yuan, with exports down 4.2 percent and imports down 8.2 percent.

Trade surplus for the first quarter widened 8.5 percent from one year earlier to 810.2 billion yuan.

Exports to the European Union, China's biggest trade partner, dropped 1.4 percent year on year in the first three months of the year, the GAC data showed.

In the same period, exports to the United States, China's second-biggest trade partner, declined 3.4 percent and exports to the Association for Southeast Asian Nations, the third-largest trade partner, dipped 8.5 percent.