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SEOUL - South Korean President Lee Myung-bak accepted Defense Minister Kim Tae-young's resignation on Thursday, according to Seoul's presidential office Cheong Wa Dae.

"President Lee decided to accept Defense Minister Kim Tae-young's intent to step down," presidential chief of staff Yim Tae-hee told a press briefing.

Kim had already expressed his intention to quit in May to take responsibility for the sinking of the South Korean naval frigate Cheongan off the nation's west coast in March, which left 46 sailors dead. However, considering a string of pending issues including follow-up measures following the Cheongan incident and an annual defense ministerial meeting with the United States, the acceptance of Kim's resignation was postponed, according to Yim.

The president decided to accept Kim's resignation Tuesday afternoon, for the discipline in the military should be revived following a series of recent accidents, Yim said.  

South Korean Defence Minister Kim Tae-Young offers condolences at a memorial altar for two dead Marines at a military hospital in Seongnam, south of Seoul November 25, 2010.[Photo/Agencies]

 Local experts said the move is aimed to hold the defense chief responsible for mishandling the military's response to the DPRK's fatal artillery shelling on a South Korean Island in waters off the west coast Tuesday, which killed four South Koreans, including two civilians.

Seoul's Ministry of National Defense has been under fire for its handling of the artillery clash, especially its belated response and "lax defense posture".

Yim said Kim's replacement will be announced on Friday, and that the presidential secretary of defense will be replaced as well.

South Korea and the DPRK exchanged fire in waters off the west coast of the divided peninsula Tuesday, during which some shells landed on South Korea's Yeonpyeong Island near the contentious sea border called Northern Limit Line (NLL). The clash left four South Koreans dead, while damages to the DPRK have yet to be verified.

South Korea and the DPRK have remained at odds on the so-called NLL, which was fixed unilaterally by the US-led United Nations Command after the 1950-1953 Korean War. South Korea holds the NLL as the de-facto western inter-Korean border, but the DPRK rejected the NLL and only recognized the demarcation line it drew in 1999, which was further south of the NLL.