Washington has presented a new alternative plan for Seoul's pledged investment of 350 billion U.S. dollars, which is now under review.

Foreign Minister Cho Hyun said during a parliamentary audit Monday that Seoul had conveyed concerns to Washington that providing the entire amount as direct investment would bring foreign-exchange strain and a significant economic impact.

Cho noted that Washington originally proposed a package including loans and guarantees, but later revised it to consist entirely of direct investment, which Seoul rejected. 

The United States has countered with an alternative proposal.

He added that both sides aim to make progress on the deal before the upcoming South Korea-U.S. summit on the sidelines of the APEC meeting later this month.