South Korea on Thursday proposed formal talks with North Korea to normalize the Gaeseong industrial park with a warning that it would take “grave action” unless the North accepted its offer by Friday morning.

North Korea suspended the joint industrial park north of the border amid heightening military tension in early April,

“We cannot let the Gaeseong industrial complex be in the current situation for the long haul,” Unification Ministry spokesman Kim Hyung-suk told a news conference.

“Accordingly we are officially proposing to North Korea to hold working-level talks between the two responsible governments to resolve humanitarian issues for workers at Gaeseong and normalize the complex.”

Seoul’s position remains steadfast that the district should be maintained and developed in a stable manner, Kim added.

“But if North Korea again rejects our offer, we will have no choice but to take a grave action.”

He did not elaborate on the measure but appeared to signal that Seoul could pull out all its 176 remaining citizens from the complex.

Losses for the factories have snowballed since the country banned the entry of South Korean people and cargo on April 4 and withdrew its 53,000 employees on April 9, effectively suspending operations.

The decision followed a weeks-long torrent of North Korean military threats since South Korea and the U.S. began military drills and the U.N. levied its strongest sanctions last month over a nuclear test.

The remaining South Koreans, mostly executives and plant managers, are subsisting on ramen, biscuits and other instant food stored as snacks for night shifts. A surging number of firms are suffering order cancelations, a client exodus and credit crunch.

Offering an olive branch, President Park Geun-hye and Unification Minister Ryoo Kihl-jae proposed dialogue two weeks ago to settle the disputes and reactivate the assembly lines.

But the intractable regime dismissed the offer, demanding Seoul and Washington first end and apologize for international sanctions and “provocations” including the military exercises.

Even so, the Unification Ministry has since requested informal talks “almost every day” with the Kaesong Industrial District Management Committee and the General Bureau for the Special Zone Development Guidance in charge of the complex, a senior official told The Korea Herald on condition of anonymity. 

“North Korea even refused to take our written demand that it allow a medical team and a minimum number of people to cross the border to clear humanitarian problems and deliver foodstuffs,” Kim said.

Whether Pyongyang will accept is unclear. It appears to have shown a letup in its nuclear threats and bellicose rhetoric but at the same time no sign of reconciliation has come from the country.

Some officials and experts have said that a war of nerves between the two Koreas would hold out at least until the annual Foal Eagle drill finishes at the end of this month.

By Shin Hyon-hee (heeshin@heraldcorp.com)