South Korean exports in May fell 10.9 percent from a year earlier while imports declined 15.4 percent, revised customs agency data showed on Monday.
The numbers were almost unchanged from the preliminary figures reported earlier.
Read More South Korea's MERS outbreak "large and complex:" WHO
South Korea is currently suffering an outbreak of Middle East Respiratory Syndrome (MERS). The country's health ministry reported five new cases on Monday, taking the total to 150.
The ministry also said a patient infected with the MERS virus had died, the 16th fatality in an outbreak that began in May.
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