A U.S. think tank says if Congress fails to vote on a bill to ratify the South Korea-U.S. free trade agreement, the strategic alliance between South Korea and the U.S. would suffer.

The U.S. Congressional Research Service said in a report that a collapse of the South Korea-U.S. FTA would probably have a profound symbolic effect, particularly upon the way South Koreans view the alliance.

The report added that if the deal is rejected or delayed, it would result in a psychological blow to many South Korean policy-makers, many of whom would likely see it as a betrayal.

The report estimated that once the trade pact takes full effect, the U.S.'s gross domestic product would expand by ten to 12 billion dollars every year.