Five Central American nations are to sign a free trade deal with South Korea on Wednesday after more than two years of talks to ease tariffs and barriers on a range of products, El Salvador's government announced.

Costa Rica, El Salvador, Honduras, Nicaragua and Panama will seal the pact with the Asian country, sending their economy ministers to the signing ceremony.

Six Central American countries had been involved in the negotiations, but one of them -- Guatemala -- was staying outside the deal at this stage.

Guatemala said it had yet to finalize trade discussions with South Korea. Belize was not involved. Talks on the pact started in June 2015 and covered 21 chapters addressing market access, rules of origin, trade facilitation, health and phytosanitary measures, trade defense, investment and technical obstacles to trade.