The South Korean defence ministry said the North had doubled its artillery units at the border and deployed 50 submarines outside their bases.
"The North is adopting a two-faced stance with the talks going on," a ministry official said.
The discussions at the border truce village of Panmunjom resumed in the afternoon after a marathon negotiating session the night before ended in the early hours without final agreement.
Analysts saw the decision to keep talking as a positive sign, with the presidential Blue House in Seoul saying the two sides would "continue to narrow down differences".
Pyongyang is threatening a concerted military attack unless Seoul switches off banks of loudspeakers that have been blasting high-decibel propaganda messages into North Korea for the past week.
Seoul says Pyongyang must first apologise for landmine explosions that maimed two members of a border patrol earlier t The North denies any role in those blasts and is extremely unlikely to apologise, while the South will not accept a compromise that might be seen to reward Pyongyang's belligerence.
"But I don't think such a vague statement will work this time," Jeung said, stressing that the case of the maimed soldiers -- both of whom lost legs -- had become an emotional issue in the South.
"So I think the best outcome of this meeting will be an agreement for another high-level meeting in the future, such as defence ministerial talks," he added.
Despite Pyongyang's past record of making dramatic but largely unrealised threats, the ultimatum sent tensions soaring to their highest level for years, with the North re-positioning artillery units and South Korean and US fighter jets flying simulated bombing runs.
The negotiations in Panmunjom, where the 1950-53 Korean War ceasefire was signed, are being led by South Korean national security adviser Kim Kwan-Jin and his North Korean counterpart Hwang Pyong-So -- a close confidante of leader Kim Jong-Un.
You’ve reached your limit of {{free_limit}} free articles this month.
Subscribe now for unlimited access.
Already subscribed? Log in
Subscribe to read the full story →
Smart Quarterly
₹900
3 Months
₹300/Month
Smart Essential
₹2,700
1 Year
₹225/Month
Super Saver
₹3,900
2 Years
₹162/Month
Renews automatically, cancel anytime
Here’s what’s included in our digital subscription plans
Exclusive premium stories online
Over 30 premium stories daily, handpicked by our editors


Complimentary Access to The New York Times
News, Games, Cooking, Audio, Wirecutter & The Athletic
Business Standard Epaper
Digital replica of our daily newspaper — with options to read, save, and share


Curated Newsletters
Insights on markets, finance, politics, tech, and more delivered to your inbox
Market Analysis & Investment Insights
In-depth market analysis & insights with access to The Smart Investor


Archives
Repository of articles and publications dating back to 1997
Ad-free Reading
Uninterrupted reading experience with no advertisements


Seamless Access Across All Devices
Access Business Standard across devices — mobile, tablet, or PC, via web or app
