China's exports tumbled 6.6 percent year-on-year to 1.14 trillion yuan (around $174 billion) in January, authorities said Monday, as the struggling manufacturing sector remained a drag on the world's second-largest economy.

Imports fell sharply 14.4 percent year-on-year to 738 billion yuan in January, Customs said. The monthly trade surplus rose 12.2 percent to 406 billion yuan.