Seoul, South Korea ? Hundreds of demonstrators blocked traffic in South Korea’s capital on Sunday to protest a U.S. free-trade agreement, and farmers on a resort island called for the deal to be scrapped, a day before the start of a new round of negotiations in the stalled talks.

Washington and Seoul have held three rounds of trade talks since June aimed at forging a deal to lower tariffs and open markets between the countries – the largest accord for the U.S. since the North American Free Trade Agreement in 1993.

The two sides have set a goal of reaching a basic agreement by the end of this year to submit to their respective legislatures. The first three rounds made slow progress after being hung up on such issues as market access and South Korean goods made in North Korea.

The negotiations are scheduled to last through Friday in Seogwipo, a city on the resort island of Jeju, located about 60 miles south of the mainland.