SEOUL (Reuters) -- South Korea, which has the third-largest contingent of foreign troops in Iraq, began on Tuesday its pullout of 1,000 of its 3,200 soldiers remaining in the country, a military official said.

South Korea had deployed 3,600 troops in Iraq in 2004 as a show of support for its closest military ally, the United States, despite opposition among the public and within President Roh Moo-hyun's progressive ruling Uri Party.

The South Korean contingent is stationed in the northern region of Arbil and has been conducting peace keeping operations and reconstruction projects.

Parliament authorized the second one-year extension of the mission at the end of 2005 but with the cut of 1,000 troops, citing what the government said had been progress made in the mission.

The first reduction of 40 South Korean soldiers came as part of a troop rotation and the cut of 1,000 troops is scheduled to be completed at the end of the year, the official at the Joint Chiefs of Staff said by telephone.

The United States has the largest contingent of foreign troops in Iraq followed by Britain. South Korean forces have suffered no casualties in Iraq.

The pullout could drop South Korean forces to fourth after Italy. Prime-minister-in-waiting Romano Prodi has said his new government may pull out its 3,000 troops after consultations with the U.S.-led coalition and Iraqi authorities.