China reported a sharp slowdown in exports last month. Imports also unexpectedly dropped, amid weakness in the domestic economy and sluggish demand overseas.
Official data showed China's inflation has slowed to 2.1% in the year to May, compared with 2.4% in April.
The world's second-largest economy has set its inflation target for this year at 3.5%, higher than the actual inflation rate 2.6% last year.
Analysts had expected the economy, which grew at its slowest pace in 13 years in 2012, to experience a pick-up this year.
