U.S. and South Korean negotiators reached agreement on April 1 (in the U.S.), as late as they possibly could, and still notify the U.S. Congress in time to take advantage of the existing U.S. trade promotion authority: S. Korea, U.S. reach free trade agreement (Yonhap News, April 2 in Korea); South Korea, U.S. Reach Free Trade Deal (AP, April 1 in the U.S.).
Evan Ramstad describes how it ended for the Wall Street Journal (U.S.-Korea Trade Deal Still Faces Hurdles (April 3):
The two countries reached the deal just before midnight, Eastern Time in the U.S., in time to reach Congress ahead of a deadline tied to the expiration of Mr. Bush's trade-negotiating powers.
With fewer than 80 minutes remaining to the U.S. deadline, South Korea Trade Minister Kim Hyun Chong left the Grand Hyatt Hotel in Seoul, where the negotiations were taking place, to meet Mr. Roh and several other cabinet ministers to discuss final terms. He called Mr. Bhatia on his way back to the hotel -- 22 minutes before the deadline -- to say the countries had a deal.
A complete draft of the deal will take a week or two, after which Messrs. Bush and Roh will have to win approval for the deal from lawmakers.
Here's a somewhat earlier Ramstad story (U.S., South Korea Reach Trade Pact, Wall Street Journal, April 2 in U.S.):