South Koreans have rallied in the capital Seoul to protest a Free Trade Agreement (FTA) with the US, saying the pact would hand over the country's economic sovereignty to Washington.
About 1,200 activists rallied in downtown Seoul on Wednesday, chanting slogans against the deal and demanding the resignation of President Lee Myung-Bak.
The rally, which was also attended by members of major opposition parties, came hours before the agreement came into force at midnight local time.
Protesters said the deal would crush South Korea's economy and hurt people's livelihood. They also complained that it would damage the country's farming and service industries by flooding the market with cheaper imports.
The activists vowed to keep protesting until the government nullifies the agreement.
Meanwhile, US President Barack Obama called his South Korean counterpart on Thursday to welcome the beginning of the agreement.
Obama thanked President Lee for his "cooperation in getting the deal implemented," claiming that the agreement serves as a good model for global free trade.
The pact, originally signed between the two countries in July 2007, was approved by South Korean parliament last November and is Washington's biggest FTA since the 1994 North American Free Trade Agreement with Canada and Mexico.