Amid rising tensions with DPRK, a spokesperson for the President of South Korea Yoon Suk-yeol said on Wednesday that the President said South Korea's national security is more than ever exposed to greater risk and that the country must excel DPRK's military capabilities. 

"President Yoon Suk-yeol said our national security is in a graver situation than ever, and that without thorough security and confidence in it, there can be no livelihood or economy," spokesman Lee Jae-myoung told a briefing, as quoted by the South Korean Yonhap news agency.

Lee added that even though the DPRK possesses nuclear weapons, the South must "perfectly overwhelm the North" in military strength, according to Yoon.

Yoon also reassured military officials that South Korea's allies will promptly respond to any situation when required.  

DPRK has been test-firing ballistic missiles since late September in reaction to the US and South Korea's unwillingness to suspend military drills near its territory, which Pyongyang regards as a dress rehearsal for war.

On Monday, Seoul's Joint Chiefs of Staff said in a statement on Monday that DPRK fired about 130 artillery shells at 2:59 pm (0559 GMT) from two distinct sites, one on the DPRK's east coast and one on the west coast. 

According to a statement issued by the South's military, some of the shells landed in a "buffer zone" near the sea border in what Seoul said was a violation of a 2018 inter-Korean agreement designed to ease tensions between the two countries.

But none of the shells crossed the Northern Limit Line, which is the de facto maritime border, according to the statement. 

DPRK quickly responded in a statement by claiming the artillery firing was a "tit for tat warning" against the provoking artillery firings by the South.

On Tuesday, it was reported that the US made a determination approving a possible Foreign Military sale to the Republic of Korea of CH-47F helicopters and related equipment for an estimated cost of $1.5 billion. 

The US' Asian ally also requested to buy 18 CH-47 Chinook helicopters and other related equipment, the Pentagon's press release added.

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