If happened, the expiry of the General Security of Military Information Agreement (GSOMIA) was to intensify discord between South Korea and the U.S., which wants its two Asian allies to keep their dispute out of security cooperation matters.
The office of South Korean President Moon Jae-in said it chose to suspend the effect of the three months' notice it gave in August to terminate the agreement after Tokyo agreed to reciprocal measures.
"Japan has expressed its understanding", Kim said in a briefing.
South Korea's pivot on GSOMIA follows progress on trade, with Japan agreeing to resume talks about export controls and Seoul pledging to drop a World Trade Organization action against Japan. "Go tell your Korean friends it is not true", one Japanese government official said as she handed out a Korean-language brochure entitled "To Eliminate Groundless Rumours", which said fish and agricultural produce from Fukushima were safe.
The military agreement, which Japan had sought to maintain, is automatically extended every year unless either country notifies the other 90 days in advance of its intention to terminate it, a deadline that fell in August.
Nearly immediately after Seoul announced in August that it would not renew GSOMIA, the USA expressed "strong concern and disappointment".
Speaking at the same Cheong Wa Dae press room three months earlier, Kim, who doubles as head of the secretariat of the National Security Council (NSC), read out a statement on Seoul's plan not to extend the pact, signed in 2016.
The agreement would have been the most significant casualty yet of a dispute between Abe and South Korean President Moon Jae-in that rapidly escalated over the past year as the US sat largely on the sidelines.
"The breakdown of the Japan-South Korea relationship makes any gesture to demonstrate the health of US alliance network extremely hard, if not impossible", said Yuki Tatsumi, director of the Japan Program at the Stimson Center in Washington.
However, he warned that the pact could still "be terminated at any time".
There's also concern that Trump, after already suspending major U.S.
South Korea's earlier decision to halt intelligence-sharing agreement came amid a bitter feud over history and trade and despite pressure from the United States to maintain a key element of their trilateral security cooperation.
A U.S. State Department representative welcomed Seoul's decision to suspend the termination of the General Security of Military Information Agreement, or GSOMIA, saying it "sends a positive message that like-minded allies can work through bilateral disputes".
It seemed neither country was ready to budge from their positions after last-minute meetings between their diplomats and military officials over the past week ended without any apparent breakthrough.
With the clock ticking, . focus is on the G20 foreign ministers' meeting which kicks off in Japan on Friday, .as it will bring together top officials from the US and Japan.
Visiting Seoul last week, U.S. Defense Secretary Mark Esper said the agreement allows fast and effective information exchanges between the three countries, which would be crucial in times of war. The three-year-old pact was seen as important because it demonstrated the neighbors' ability to cooperate independently from Washington to counter shared threats including China and North Korea.
It took years for the United States to persuade South Korea and Japan to sign the GSOMIA, which was created to facilitate direct intelligence-sharing between the Asian U.S. allies.
The GSOMIA pact, signed in 2016, enabled the two United States allies to share military secrets, particularly over Pyongyang's nuclear and missile capacity.