By Lee Tae-hoon

Opposition parties Sunday vowed to block the National Assembly’s endorsement of the revised free trade deal (FTA) with the United States, saying the government has made excessive concessions in the “humiliating negotiation”.

Citing a report, Sohn Hak-kyu, chairman of the main opposition Democratic Party (DP), estimated that Seoul made concessions worth 3 trillion won ($2.64 billion) to Washington in return for new demands worth 300 billion won.

The DP leader said that his party is mulling over whether to demand a complete revision of the bilateral trade deal in an attempt to seek revisions in the ratchet clause that bars going back to the pre-FTA days and the investor-state dispute (ISD) system, which allows investors to file suits against each other’s government for possible unfair treatment.

DP floor leader Park Jie-won said his party will join forces with civic groups and other opposition parties, including the Liberty Forward Party (LFP), to address the problems of the revised bilateral trade deal in an attempt to block its parliamentary ratification.

“Our party cannot tolerate the disgraceful negotiation process and will not accept the lopsided deal,” Park said shortly after Trade Minister Kim Jong-hoon’s briefing on the results of the FTA renegotiation.

Opposition parties pointed out that the timing of the renegotiation was ill-guided as it took place when the nation’s security heavily depends on U.S. forces and inter-Korean tensions reached a new peak due to Pyongyang’s artillery attack on Yeonpyeong Island on Nov. 23.

“The government failed to protect the nation’s interests by holding the talks at a time when it desperately needs military cooperation from the United States,” the LFP said in a statement.

The governing Grand National Party (GNP) urged opposition parties to support the parliamentary approval of the revised free trade deal, claiming that it was a "win-win" situation for both countries.

"We see the deal as a mutually beneficial accord for both countries," said Rep. Ahn Hyoung-hwan, spokesman of the GNP, said.

"The GNP will make the utmost efforts to have the FTA pass smoothly at the National Assembly.”

Ahn noted, though Seoul made concessions in the auto industry, that Seoul has also produced substantial “practical gains" from it, such as Washington’s concessions to extend a 25 percent tariff on U.S. pork imports to 2016, two years later than the previous deadline.

He claimed that it would not deal a severe blow to domestic automakers, given that U.S. cars have a small market share in Korea anyway.