Citizens of Dongducheon, north of Seoul, will hold a mass rally this week to protest a recent South Korea-U.S. deal to retain an American artillery brigade in the city, a local civic group said Sunday.

Last month, Seoul and Washington agreed to retain the 210th Fires Brigade under the 2nd Infantry Division in Dongducheon near the tense inter-Korean border until "the mid-2020s" to bolster deterrence against North Korea.

A 2004 bilateral deal had called for relocating the U.S. military unit to a new location south of the Han River that runs through the South Korean capital, by the end of 2016.

The latest agreement has pulled the plug on the city's plan to develop the land to be vacated by U.S. troops, sparking anger among citizens in Dongducheon.

The civic group said the protest rally will be held in front of the 2nd Infantry Division on Wednesday, but it didn't disclose how many citizens will participate.

"We cannot but express anger at the agreement that was unilaterally reached without previous consultations with Dongducheon citizens," the group said in a statement. "The deal is an act that totally disregards the citizens of Dongducheon."

The civic group said U.S. forces have been stationed in Dongduchoen for 60 years, which has stigmatized it as "a military town."

Due to the existence of the U.S. military unit, Dongducheon has been suffering more than 320 billion in economic losses annually, including 43 billion won in lost local tax revenue, it said, urging the South Korean government to offer financial assistance to the town.

On Wednesday, the city's council issued a statement calling for the relocation of the U.S. military division as agreed earlier and launched a solo sit-in in front of the division's main gate.

The brigade's artillery, including the Multiple Launch Rocket System (MSLR) and the ATACMS surface-to-surface missile system, is seen as a strong deterrent to North Korea's long-range artillery threats.    

Some 28,500 American troops are stationed in South Korea to help defend its Asian ally from aggression by North Korea, a legacy of the 1950-53 Korean War that ended in a truce, not a peace treaty. (Yonhap)