South Korea did not participate in the 2006 agreement, but showed interest in entering the TPP, and was invited to the TPP negotiating rounds in December 2010 by the U.S. after the successful conclusion of its Free trade agreement between the United States of America and the Republic of Korea. South Korea already had bilateral trade agreements with some TPP members, but areas such as vehicle manufacturing and agriculture still needed to be agreed upon, making further multilateral TPP negotiations somewhat complicated. South Korea may join the TPP as part of a second wave of expansion for the trade agreement.