This photo, carried by Pyongyang's official Korean Central News Agency (KCNA) on June 1, shows the launch of North Korea's first military spy satellite the previous day. Yonhap

South Korea threatened, Monday, to implement retaliatory measures if North Korea pushes ahead with its planned launch of a military spy satellite, sending a rare yet strong warning against Pyongyang's envisaged military action.

Although the military did not specify what measures it could take, analysts believe that South Korea's next move is most likely to involve the partial suspension of an inter-Korean military pact signed on Sept. 19, 2018, also known as the Comprehensive Military Agreement (CMA).

Military authorities anticipate that the launch — which would be the North's third attempt following two botched endeavors earlier this year — could take place as early as this week.

"The North Korean regime must face the stark reality of unanimous condemnation by the international community over its illegal actions. We strongly warn them to immediately cease the ongoing preparations for the launch of a military reconnaissance satellite," Lt. Gen. Kang Ho-pil, chief director of operations at the Joint Chiefs of Staff (JCS), said during a media briefing.

"If North Korea proceeds with the launch despite the warning, our military will take necessary measures to protect the safety of our people," he added, without elaborating on what specific measures Seoul plans to take.

Monday's announcement by the JCS was unusual in that South Korea normally condemns North Korea's military provocations after they take place, rather than issuing a warning in advance.

Experts said the rare warning issued through a public briefing can be seen as a preliminary step to scrap the 2018 inter-Korean military agreement.

The military agreement, signed by the previous Moon Jae-in government, has been criticized by the incumbent administration for restricting South Korea's reconnaissance capabilities near the border.

"It is extremely rare for the government to issue a warning before North Korea conducts a military provocation. It seems that the announcement was aimed at developing a rationale to nullify the military pact if North Korea proceeds with the satellite launch, a position held by our military since Defense Minister Shin Won-sik took office," said Shin Jong-woo, a senior researcher at the Korea Defense and Security Forum, a think tank.

Lt. Gen. Kang Ho-pil, chief director of operations at the Joint Chiefs of Staff (JCS), speaks during a briefing at the Ministry of National Defense headquarters in Seoul, Monday. Yonhap

During Monday's briefing, Kang mentioned that Pyongyang violated the inter-Korean military agreement more than 3,400 times so far, beginning with artillery fire drills conducted in November of 2019 on the islet of Changrin near the maritime border separating the two Koreas, which is called the Northern Limit Line (NLL).

"The behavior exhibited by North Korea so far clearly indicates a lack of any willingness to comply with the agreement," Kang said.

However, the South Korean military did not immediately confirm whether the "neccessary measures" would involve the suspension of the military agreement.

"It is not a matter for the JCS to decide. We believe it is an issue that will be addressed after a review by related government agencies," a JCS official told reporters during a closed-door briefing later in the day.

Park Won-gon, a professor of North Korean studies at Ewha Womans University, also viewed that the warning reflects the South Korean government's intention to partially suspend the military pact following the North Korean satellite launch.

But at the same time, the professor stressed that the South Korean government should be prudent about making the first move to scrap the agreement, which may come at the cost of increased military tensions on the Korean Peninsula.

"I do agree that the agreement limits reconnaissance capabilities and some of the clauses of the pact are flawed. But there are some positive aspects of the military agreement, such as bringing stability to the NLL," he said.

"Plus, if the South becomes the first one to officially declare the end of the agreement, it could raise eyebrows in the international community," Park added.

Another expert on North Korea, asking not to be named, said South Korea could face a dilemma over the suspension of the Sept. 19 agreement.

"I think the government has not properly reviewed the consequences of suspending the military agreement. Once scrapped, there's no going back," he said. "And from what I understand, the United States does not support the idea of suspending the agreement. The U.S. doesn't want more tensions on the peninsula."

During a joint press conference with South Korea's defense minister in Seoul last week, U.S. Defense Secretary Lloyd Austin said the two sides "agreed to stay in close consultation going forward" on the suspension of the military agreement.