President Yoon Suk-yeol speaks to reporters as he arrives at the presidential office in Seoul on Friday. (Yonhap)

South Korea’s National Security Council on Friday strongly condemned North Korea for carrying out a series of military provocations overnight, including an artillery drill in violation of an inter-Korean military agreement.

Early on Friday, Pyongyang fired some 170 artillery shots into maritime “buffer zones” in the east and west coast. It also launched a short-range ballistic missile toward the East Sea.

Prior to the launch of the ballistic missile and artillery shots, the North flew about 10 warplanes staging a menacing flight close to the inter-Korean border, prompting the South Korean Air Force to send its F-35A stealth fighters to the scene.

Over the barrage of provocations, the National Security Council held an emergency meeting to discuss response measures.

Top security officials, including National Security Advisor Kim Sung-han and ministers, noted how the recent ballistic missile tests by the North came with an unprecedented frequency and were fired from various places at different times. They agreed that the recent provocations clearly constituted a violation of the United Nations Security Council resolutions, the presidential office said.

South Korean President Yoon Suk-yeol on Friday said the North’s artillery firing is a violation of the Comprehensive Military Agreement signed between the two Koreas in 2018, which calls for both sides to halt of all hostile military activity.

"We're reviewing the cases one by one, but we are sure it is a violation of the Sept. 19 accord,” Yoon said.

To a media inquiry, the US State Department also confirmed that the series of provocations carried out by the North overnight on Friday is a clear violation of the UNSC resolution, threatening the security on the Korean Peninsula and the surrounding regions.

Seoul’s top nuclear envoy held separate phone calls with his US and Japanese counterparts to agree that the overnight provocations by Pyongyang is a violation of the UNSC resolution as well as the inter-Korean accord, according to the Foreign Ministry.

Kim Gunn, Seoul's special representative for Korean Peninsula peace and security affairs, also reaffirmed the commitment to deter North Korean threats in his talks with Washington’s special representative for North Korea Sung Kim, and Takehiro Funakoshi, director general for Asian and Oceanian affairs at Japan’s Foreign Ministry.