SEOUL, South Korea (CNN) -- Troubled relations between North and South Korea suffered a fresh blow Friday after Seoul decided to withdraw all its remaining citizens from the manufacturing zone jointly operated by the two.

The televised announcement by South Korean Unification Minister Ryoo Kihl-jae followed North Korea's dismissal of a request for talks about the deteriorating situation at Kaesong Industrial Complex.


Pyongyang halted activity at the complex this month amid heightened tensions in the region.

The South Koreans' imminent departure bodes ill for the future of the zone, the last major symbol of cooperation between the two countries. It had continued to operate throughout previous inter-Korean tensions during the past eight years.

In the past two months, tensions on the Korean Peninsula has been rich in saber-rattling and short on concrete actions.

But the Kaesong complex, which is on the North's side of the border and houses the operations of more than 120 South Korean companies, appears to have become a significant victim.

Growing suffering

Ryoo said the decision to withdraw the roughly 175 South Koreans was a result of their "growing suffering caused by the unjust actions of the North," which has been preventing workers, as well as food and medical supplies, from crossing the border into the zone for the past several weeks.

In an apparent last ditch attempt to resolve the crisis Thursday, South Korea proposed formal talks with the North, warning of serious consequences if the offer was rejected.

'Deceptive' offer rejected

But the North spurned the proposal.

In a statement on state media Friday, a spokesman for the North Korean National Defense Commission described Seoul's offer of talks about the complex as "deceptive."

It said that if Seoul "keeps aggravating the situation," it would "be forced to take the final decisive and crucial measure first."

The South Koreans who remain in the complex are believed to have been looking after the idle factories there. Ryoo said Friday that the South Korean government would support the companies invested in the complex so they can continue with their business activities.

Suspending activity

Earlier this month, during a frenzy of fiery rhetoric directed at South Korea and the United States, the North began blocking South Koreans from entering the complex across the heavily fortified border.

It then pulled out the more than 50,000 North Koreans who work in the zone's factories, saying it was temporarily suspending activity there. The move surprised some observers since Kaesong was considered to be a key source of hard currency for the regime of Kim Jong Un.

The situation on the Korean Peninsula deteriorated after the North carried out its latest underground nuclear test in February, prompting the U.N. Security Council to tighten sanctions on the regime in Pyongyang.

The tougher sanctions, together with joint U.S.-South Korean military training exercises in South Korea, intensified North Korea's threats against Washington and Seoul.

The North's ominous language, which unnerved the United States enough for it to move missile-defense systems into the region, had appeared to calm somewhat recently. And the U.S.-South Korean military exercises are due to end in the coming days.

Remarks against 'U.S. imperialists'

But at an event to celebrate the anniversary of the creation of the North Korean military on Thursday, senior officials made remarks that revived the theme of nuclear attack against "U.S. imperialists," something the North repeatedly used in its rhetoric over the past two months.

'One click away'

North Korean pilots "once given a sortie order, will load nuclear bombs, instead of fuel for return, and storm enemy strongholds to blow them up," the state-run news agency cited one commander, Ri Pyong Chol, as saying at the event in Pyongyang on Thursday.

And Strategic Rocket Force Cmdr. Kim Rak Gyom was reported as saying that North Korea's "inter-continental ballistic missiles have set the dens of the brigandish U.S. imperialists as their first target and officers and men of the Strategic Rocket Force are one click away from pushing the launch button."

Earlier this month, a U.S. congressman disclosed a Defense Intelligence Agency assessment that judged with "moderate confidence" that the North can deliver a nuclear device with a missile, though with "low" reliability.

But James Clapper, the director of national intelligence, later told the Senate Armed Services Committee that other U.S. intelligence agencies don't share the DIA's conclusion.

CNN's K.J. Kwon reported from Seoul, and Jethro Mullen reported and wrote from Hong Kong.