South Korea and the European Union (EU) still have remaining issues to discuss on, including duty drawback scheme, before sealing their free trade pact, South Korea's trade minister said on Thursday.

"As duty drawbacks are allowed under the World Trade Organization and our competitors in the European market also have this scheme, we need to have more talks to narrow differences on the issue," Kim Jong-hoon, South Korean trade minister, said on a local radio program.

The two countries announced earlier on Tuesday that they reached a tentative free trade pact after their final round of negotiation talks and that the deal will be finalized early next month.

However, the two sides still show different stances over the issue of duty drawback scheme, under which South Korean firms, which use imported materials to make export products, would be returned import tariffs.

While South Korea is strongly requesting its counterpart on the matter, the EU opposes it on the ground that it does not allow the scheme under existing free trade accords with Mexico and Chile.

At next month's minister-level meeting, the two countries are also expected to narrow differences on rules of origin, with both sides known to have compromised on the marginal mark at 45 percent in order to acknowledge a product to be virtually made in the partner country.

South Korean Trade Minister Kim is scheduled to meet his EU counterpart Catherine Ashton in London on April 2 to finalize the deal.

If the agreement is sealed, South Korea's exports are expected to increase by US$11 billion and gross domestic product by 3.08 percent, according to a forecast by the Korea Institute for International Economic Policy.