A round of heated debates over the effects of the South Korea-U.S. free trade agreement (FTA) is expected in the U.S. capital this week, as the two sides mark the first anniversary of the implementation of the historic deal.

After years of political controversies and tumultuous ratification procedures, the agreement, dubbed "KORUS FTA," went into effect on March 15 last year. It is arguably the U.S.'s most commercially significant free trade agreement in almost two decades.

South Korea's opposition lawmakers argued it's more in favor of the U.S. business community, saying it would deal a blow to many South Korean economic sectors.

Data so far, however, suggest South Korea is generally benefiting more.

The U.S. trade deficit with South Korea has soared to the highest point under the FTA, according to statistics from the U.S. International Trade Commission (USITC).

January's U.S. trade deficit with Korea topped $2.4 billion -- the largest monthly deficit with Korea on record, the agency said in its monthly trade data released last week.

While U.S. goods imports from all countries rose 3 percent in January, U.S. imports from Korea soared 18 percent, it added.

"The U.S.-Korea trade imbalances of recent months are remarkable not just in comparison with most other U.S. trade partners, but in comparison to how U.S. trade with Korea looked before the Korea FTA took effect in March of last year," said Public Citizen, a consumer advocacy group based in Washington.

U.S. and South Korean officials ostensibly say it's still premature to conclude which side is gaining more from the agreement.

The U.S. authorities, however, have begun a full-scale work to assess the impact of the KORUS FTA on domestic industries and study ways to maximize benefits for them, according to informed sources.

The Office of U.S. Trade Representative (USTR) requested the USITC submit a detailed report on the issue by May 1.

The USITC is scheduled to hold a relevant hearing throughout Thursday, a source said.

On Tuesday, former government officials and experts will sit together to share their experience and views on the KORUS FTA.

They include Kathleen Stephens, former U.S. ambassador to South Korea; Karan Bhatia, former deputy USTR; and Scott Miller, a senior researcher at the Center for Strategic and International Studies (CSIS).

South Korean Ambassador to the U.S. Choi Young-jin plans to deliver welcoming remarks at the event, co-hosted by the CSIS and the Korea Economic Institute of America.

The U.S. Chamber of Commerce and the U.S.-Korea Business Council will hold a separate event on Friday.

Participants will include Wendy Cutler, the assistant U.S. Trade Representative for Japan, Korea and APEC affairs.

She led the U.S. negotiating team for the KORUS FTA that was signed in 2007.

Following her keynote speech, experts will discuss the extent of progress under the pact over the past year.

In an interview with Yonhap News Agency in January, Cutler emphasized the importance of a longer-term evaluation of its "actual results."

She was confident that it would prove to be a "win-win" mechanism, a view with which South Korean trade officials agree.

Anthony Kim, a veteran policy analyst at the Heritage Foundation, agreed that it's too early to be skeptical.

"Over the past year, the two-way interaction between the U.S. and Korea has become more dynamic, laying out foundations for greater economic engagement in both goods and services," he said.

More importantly, he added, the first year has served as a critical legal and regulatory infrastructure-building period in which private companies in both countries have been learning how to take advantage of the KORUS FTA, working out initial entry points to corresponding markets, and competing with various market strategies for the future.

Miller, a senior advisor at the CSIS, also expressed optimism.

"The two economies are complimentary to each other, and the KORUS FTA provides the basis for deeper ties in trade, investment and production sharing," he said. "In my judgment, bilateral economic relations are the best they have been in over a decade."