South Korean exporters are being confronted with growing requests to verify the country of origin on their products as major economies toughen import rules amid a prolonged economic slowdown, the customs office said Sunday.

According to the Korea Customs Service, 153 such requests from foreign importers were filed this year, accounting for nearly 60 percent of the total 258 requests submitted between 2008 and 2012.

In particular, requests from the European Union more than tripled to 135 cases in the first eight months of this year from last year’s 41. South Korea’s free trade deal with the EU took effect in July last year.

A country-of-origin verification request is designed to prevent unfair trade by companies from signatories to a free trade agreement.

Over the past five years, South Korean auto parts received the largest 51 requests for country-of-origin verification, followed by petrochemicals with 48, textiles and clothing with 42 and general machinery with 33.

The customs office said South Korean exporters may face more country-of-origin requests next year as the United States is expected to toughen related rules. The FTA between South Korea and the U.S. went into effect in March of this year.

The office also said South Korean exporters are faced with increasing import barriers in the United States and other major economies.

As of the end of September this year, the U.S. and 20 other countries had imposed a combined 120 import regulations on South Korean companies, including anti-dumping duties and safeguard measures, according to the office. (Yonhap News)