South Korea's exports rose 36.1 percent on-year in the first 20 days of October on the back of robust demand for chips, petroleum products and autos, customs data showed Thursday.

The country's outbound shipments stood at $34.2 billion in the Oct. 1-20 period, compared with $25.1 billion a year earlier, according to the data from the Korea Customs Service.

Imports increased 48 percent on-year to $36.7 billion, resulting in a trade deficit of $2.49 billion during the cited period, the data showed.

By sector, outbound shipments of memory chips, a key export item, rose 23.9 percent on-year and those of autos increased 10.5 percent over the cited period.

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 rival SK hynix Inc.

Autos made up around 7 percent of total exports.

Exports of petroleum products soared 128.7 percent over the cited period as oil prices remained high amid the global economic recovery.

By country, shipments to China, South Korea's largest trading partner, rose 30.9 percent on-year, and those to the United States gained 37.1 percent.

The South Korean economy is on a recovery track on the back of robust exports.

Exports, which account for half of the economy, grew 16.7 percent on-year in September, extending their gains to the 11th straight month.

The Bank of Korea forecast Asia's fourth-largest economy to grow 4 percent this year. The government forecast economic growth of 4.2 percent. (Yonhap)