South Korea's exports rose 28.7 percent in the first 10 days of May from a year earlier on the back of demand for chips and petroleum products, but the trade deficit widened over high global energy prices, customs data showed Wednesday.

The country's outbound shipments stood at $16.1 billion in the May 1-10 period, compared with $12.5 billion a year earlier, according to the data from the Korea Customs Service.

Imports jumped 34.7 percent on-year to $19.78 billion, resulting in a trade deficit of $3.72 billion during the cited period. The comparable figure for last year was $2.21 billion, the data showed.

Dubai crude, South Korea's benchmark, rose to $106.06 per barrel on average so far this month from $65.06 a year earlier.

South Korea depends on imports for most of its energy needs, and imports of crude oil and gas surged 53.7 percent and 52.7 percent, respectively, on-year during the first 10 days of May, according to the data.

By sector, outbound shipments of memory chips, a key export item, rose 10.8 percent on-year.

Semiconductors accounted for about 20 percent of exports by South Korea, home to Samsung Electronics Co., the world's largest memory chip maker, and its smaller local rival SK hynix Inc.

Exports of petroleum products more than tripled on-year as oil prices spiked amid the ongoing conflict surrounding Ukraine.

Overseas sales in auto parts advanced 13.8 percent, while those of autos fell 20.6 percent. Exports of telecommunication products also fell 27.2 percent on-year, the data showed.

By country, shipments to China, South Korea's largest trading partner, grew 9.6 percent on-year, and those to the United States jumped 30.1 percent. Exports to the European Union also rose 27.1 percent, according to the data.

Last month, the country's exports grew 12.6 percent on-year to stand at $57.69 billion, the highest tally for any April ever. It also marked the 18th consecutive month that the country's exports have logged an on-year expansion.

But the country posted a trade deficit for the second consecutive month in April as high energy prices pushed up the country's imports. (Yonhap)