South Korea and the United States on Monday began their annual two-week joint war exercise, the Combined Forces Command (CFC) said, amid North Korea's unusual low-key stance to the war game that they strongly condemned in the past.

The computer-aided Ulchi Freedom Guardian (UFG) kicked off for a 12-day run, mobilizing about 50,000 South Korean forces and approximately 30,000 U.S. servicemen, including some 3,000 from the U.S. and other bases in the Pacific region.

The CFC said the drills are intended to examine the forces' ability to secure security on the Korean Peninsula and maintain the joint defense capacities between the two allies.

The training is expected to include defense drills against North Korean provocations and cyber attacks that target the military network as well as contingencies involving weapons of mass destruction, according to military officials. 

Neutral Nations Supervisory Commission observers will monitor the exercise along with seven United Nations Command (UNC) states -- Australia, Britain, Canada, Denmark, France, New Zealand and Norway.

Ahead of the joint war game this year, North Korea has unusually kept a low profile, presumably due to growing signs of better inter-Korean relations.

Pyongyang has long balked at the annual UFG drills and other similar joint maneuvers, claiming they are a prelude to war despite Seoul and Washington's argument that they are for defense purposes only.

On Wednesday, both countries reached a dramatic agreement to reopen their joint factory park in the North Korean border town of Kaesong after the industrial complex was shut down in April amid rising tensions.

Efforts are also gaining pace among the participant countries to resume the long-stalled six-party talks, designed to persuade the communist country to discard its nuclear programs.

Along with the war exercise, the South Korean government will also hold a separate four-day emergency exercise from Monday.

The annual local drill, involving administrative bodies and public employees nationwide, is designed to examine the government's readiness for dealing with potential terrorist attacks and military provocations from the North.

The Koreas remain technically at war because the 1950-53 Korean War ended in an armistice. About 28,500 U.S. soldiers are stationed in South Korea. (Yonhap News)