North launches a military spy satellite, called Malligyong-1, on a new-type Chollima-1 rocket, Nov. 22, in this photo provided by North Korea's official Central News Agency. Yonhap

North Korea said Thursday it will immediately restore all military measures halted under a 2018 inter-Korean military accord after South Korea suspended part of the tension reduction deal following the North's launch of a military spy satellite.

The North's defense ministry said it will "never be bound" by the military agreement any more, effectively scrapping the deal that calls for a series of tension reduction measures along the heavily armed border, and warned that the South must "pay dearly" for its decision.

"We will immediately restore all military measures that have been halted according to the North-South military agreement," the ministry said in a statement carried by the official Korean Central News Agency (KCNA).

"We will withdraw the military steps, taken to prevent military tension and conflict in all spheres including ground, sea and air, and deploy more powerful armed forces and new-type military hardware in the region along the Military Demarcation Line," it said.

South Korea must "pay dearly for their irresponsible and grave political and military provocations that have pushed the present situation to an uncontrollable phase," the North said.

South Korea partially suspended the 2018 inter-Korean military accord, after North Korea launched a military spy satellite, called the Malligyong-1, on a new type of Chollima-1 rocket Tuesday night. The move allowed Seoul to immediately restore reconnaissance and surveillance operations near the border with North Korea.

Defending the satellite launch as a "legitimate" exercise of a right to self-defense, North Korea denounced the South for partially suspending the agreement for "unreasonable and illogical" reasons.

"Those of the 'ROK' will be held wholly accountable in case an irretrievable clash breaks out between the north and the south," the ministry said, using the acronym of South Korea's full name, the Republic of Korea.

The statement came hours after North Korea fired an unspecified ballistic missile toward the East Sea Wednesday night. The South's military said the launch appears to have failed.

N. Korea fires ballistic missile toward East Sea, but launch apparently failed: S. Korean military 2023-11-23 03:32  |  North Korea Partial suspension of 2018 military agreement 'minimum defensive measure': defense chief 2023-11-23 11:06  |  North Korea US says S. Korea's partial suspension of 2018 inter-Korean military accord 'prudent,' 'restrained' move 2023-11-23 09:23  |  Defense S. Korea to resume surveillance flights near border after 5 years 2023-11-22 16:54  |  Defense

The agreement, signed Sept. 19, 2018, under the previous liberal administration of President Moon Jae-in, calls for setting up buffer zones and no-fly zones near the inter-Korean border in a bid to prevent accidental clashes between the two Koreas.

Defense Minister Shin Won-sik pushed for suspending the deal, citing its impact on limiting South Korea's aerial surveillance capabilities.

North Korea had violated the accord 17 times until end-2022, and 15 violations occurred last year alone, including five North Korean drones' infiltration into the South in December, according to Seoul's defense ministry.

South Korea's unification ministry denounced the North Korean defense ministry's statement as a "far-fetched" claim, and "strongly" condemned Pyongyang's threat to deploy new weapons along the border.

"Seoul's partial suspension of the military accord is a just and self-defense measure that can be taken at a minimum at a time when the North has constantly violated the deal and continued its nuclear and missile threats and provocations against us," a ministry official told reporters.

He warned North Korea will face an "overwhelming and stern" response by the South if it stages provocations in border areas, and stressed Seoul is also open to talks with Pyongyang to discuss ways to defuse military tensions.

The official said North Korea has intent to "effectively nullify" the deal, but the South Korean government does not regard the accord as being scrapped.

North Korean leader Kim Jong-un, second from right, visits the Pyongyang General Control Center of the North's National Aerospace Technology Administration, Nov. 22 in this photo provided by North Korea's official Central News Agency. Yonhap

North Korea claimed it has successfully put a military spy satellite into orbit and vowed to launch several more satellites within a short span of time to better reconnoiter South Korea and "the region of its operational interest."

The launch followed its two failed attempts in May and August and came amid suspicion that Russia may have provided technical assistance for the North's spy satellite in return for Pyongyang's supply of artillery and munitions for use in its war in Ukraine.

The North said the satellite took pictures of Andersen Air Force Base and Apra Harbor in the U.S. territory of Guam on Wednesday morning. It said the satellite will officially begin its mission on Dec. 1 after a "fine-tuning process" that could take up to 10 days.

Hong Min, a senior research fellow at the Korea Institute for National Unification, said North Korea could resume military activities swiftly as early as Thursday, including drone-based surveillance operations and opening gun posts at its coastline.

"If clashes occur between the two Koreas, North Korea could flex its military muscles simultaneously in terms of conventional arms and weapons capable of mounting tactical nuclear warheads," he added.

Experts said a spy satellite will help the North stage a precision strike against targets in war situations, as it will enhance the country's surveillance capability, but many still have doubts about the North's satellite capabilities. (Yonhap)