Roughly three quarters of the 175 South Koreans still at a shuttered factory park in North Korea are scheduled to return Saturday after Seoul decided to withdraw them over Pyongyang's rejection of its demand for talks on the last symbol of inter-Korean cooperation, the government said.

The industrial complex in the border city of Kaesong bustled with more than 53,000 North Korean workers and 800 South Korean managers before Pyongyang pulled its entire work force out and banned South Koreans from entering it earlier this month.

The park, the biggest employer in Kaesong with a population of 200,000 according to North Korean officials, is the most significant casualty in the recent deterioration of ties between the Koreas. Operating with South Korean know-how and technology and with cheap labor from North Korea since 2004, it has weathered past cycles of hostility between the rivals, including two attacks blamed on North Korea in 2010 that killed 50 South Koreans.

On Thursday, Seoul issued a Friday deadline for North Korea to respond to its call for talks because it was worried about its workers not having access to food and medicine. North Korea hasn't allowed South Korea to send supplies to its managers in Kaesong since the ban.

Just hours after Pyongyang dismissed Seoul's demand for talks as "deceptive," Ryoo Kihl-jae, South Korea's top official on relations with North Korea, said Friday in a televised statement his government decided to pull all the remaining South Koreans in Kaesong.

"We've made the inevitable decision to bring back all the remaining personnel in Kaesong for the protection of our people as their difficulties continue to grow," Unification Minister Ryoo said, urging the North to protect the property of South Korean companies at Kaesong and ensure the safe return of South Koreans home.

His ministry said later Friday in a text message that 127 of the remaining South Koreans in Kaesong would return Saturday. The remaining workers are expected to leave Kaesong on Sunday.

In Friday's statement, a spokesman for the North's powerful National Defense Commission promised the workers' safety if they withdrew, while lashing out at Seoul over ongoing U.S.-South Korean military drills and the spreading of anti-North Korea leaflets at the border as proof of Seoul's insincerity.

"If they are truly worried about the lives of South Korean personnel in the (complex), they may withdraw all of them to the south side where there are stockpiles of food and raw materials and sound medical conditions," said the statement carried by official media.

"If the South's puppet group looks away from reality and pursues the worsening of the situation, we will be compelled to first take final and decisive grave measures," it said.

Impoverished North Korea has objected to views in South Korea that the Kaesong park is a source of badly needed hard currency. South Korean companies paid salaries to North Korean workers averaging $127 a month, according to South Korea's government. That is less than one-sixteenth of the average salary of South Korean manufacturer workers.

The complex, conceived following the historic 2000 summit between late North Korean leader Kim Jong Il and late South Korean President Kim Dae-jung, broke ground in 2003. The plan was for South Korean firms to build 500 factories as part of a pledge to help develop North Korea's economy, Pak Chol Su, vice director of the General Bureau for Central Guidance, which manages Kaesong, told the Associated Press in September.

The statements on Kaesong this week follow what had been something of a lull after a weeks-long tirade of warlike North Korean rhetoric that included threats of nuclear war and missile strikes. Tension rose as Seoul responded with its own tough language to Pyongyang's outburst, which was unusually violent, even by the standards of the already hostile relationship between the Koreas.

"This is a war of pride between the Koreas, but they are conducting it while leaving some room for talks," Lee Hochul, a political science professor at Incheon National University in South Korea, said, adding neither side is mentioning a permanent shutdown of the industrial complex.

Meanwhile, North Korea said Saturday it will soon put a detained American on trial for allegedly trying to overthrow the government, further complicating its already tense relations with the United States. Earlier in Washington, Republican and Democratic lawmakers introduced a bill calling for the punishment of companies, banks and governments that engage in illicit dealings with North Korea. Pyongyang has already come under a series of U.N. and U.S. sanctions for its three nuclear tests since 2006, including the latest in February.

In South Korea, regular U.S.-South Korean military drills, which Pyongyang complained bitterly about, are set to end Tuesday.

"Even at this moment, South Korea is ramping up the intensity of coastal landing drills with the United States in the east, driving the already tense situation to a point of explosion," North Korea said in its statement, complaining about alleged South Korean military plans in the event the North held the Kaesong managers hostage.