S. Korea's Park Hardens Line with North, Demands Apology

South Korea's president hardened her line with North Korea on Monday, demanding an unequivocal apology for recent provocations as the two rivals struggled to negotiate their way out of a dangerous military standoff.

As grueling talks between top negotiators from both sides entered a third day in the border truce village of Panmunjom, Park Geun-Hye insisted on North Korea making a sincere gesture of contrition for mine blasts this month that maimed two South Korean soldiers.

North Korea "should make a clear apology... and ensure that there will be no further provocations," Park said in televised comments to a meeting of senior aides.

Otherwise, she added, Seoul would continue the border propaganda broadcasts that have infuriated Pyongyang and prompted threats of concerted military strikes by the North Korean army.

The current standoff has already triggered a rare exchange of artillery fire across the border, with both sides ramping up the military rhetoric and flexing their weaponry.

In the remarks to her aides, Park stressed that there would be "no retreat" in the face of North Korean threats.

- No rewards - 

Park has maintained a strong line on North Korea since she came to office, and will push back hard against any compromise that might be seen as rewarding Pyongyang's provocations.

The talks that began Saturday in Panmunjom between top aides to both countries' leaders have so far failed to thrash out a mutually acceptable way to de-escalate the situation, despite two all-night sessions.

The North has denied any role in the recent mine blasts and analysts say it will never accede to the apology demand.

"And President Park knows that of course," said Yang Moo-Jin, a professor at the University of North Korean Studies in Seoul.

"Both sides are really just trying to ramp up pressure on the other, looking for an upper hand in what are clearly very tough negotiations," Yang said.

Pyongyang also appeared to seeking greater leverage, with the South's defence ministry saying the North had doubled the number of its artillery units at the boder, and put two-thirds of its 70-strong submarine fleet to sea.

"The North is adopting a two-faced stance with the talks going on," said a ministry spokesman who described the scale of the submarine deployment movement as "unprecedented".

- Regional concerns - 

The crisis is being eyed with mounting concern by neighboring countries and beyond, with China and Japan calling for restraint and U.N. Secretary General Ban Ki-moon urging both sides to "redouble" their efforts to reach a compromise.

Meanwhile, the United States, which has nearly 30,000 U.S. troops permanently stationed in South Korea, has pledged its commitment to the defense of its key Asian ally.

Seoul and Washington are reviewing the possible deployment of "strategic U.S. military assets" on the peninsula, the South Korean defense ministry said, without elaborating.

Technically, the two Koreas have been at war for the past 65 years, as the 1950-53 Korean War ended with a ceasefire that was never ratified by a formal peace treaty.

The talks in Panmunjom, where the 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 confidant of leader Kim Jong-Un.

The marathon sessions reflected the size of the task facing the negotiators as they seek to bridge apparently irreconcilable positions.

"Any resolution of issues now on the table will require a bold decision from their leaders," said Yang Moo-Jin, who nevertheless expressed a degree of optimism.

"The fact that they are still talking shows a genuine determination to get something out of this -- the only question is what," he said.

One option would be an agreement to open a regular high-level dialogue, but that would still leave open the issue of the propaganda broadcasts, which Seoul has vowed to continue.