China's exports to North Korea shrank 13.5% in January-February from a year earlier, Chinese customs data showed on Wednesday, reversing the robust three-digit growth seen in December.

Shipments to North Korea last month declined 15% from a year earlier to $93.7 million, a faster pace than the 12.5% drop in January, data released by China's General Administration of Customs showed.

In December, shipments grew 109% year-on-year.

Chinese Customs typically does not explain why trade with North Korea fluctuates.

Processed hair and wool for use in wigs, polyethylene, cigarettes and soybean oil were the major Chinese shipments to the reclusive state in February.

In late January, North Korea and China agreed to strengthen tactical cooperation and defend common interests, the North's official KCNA news agency said on Jan. 27. (Reporting by Ellen Zhang and Ryan Woo; Editing by Kim Coghill)