General Motors is already scaling back operations in South Korea ahead of an announced plant closure there in May.

Three days before announcing the shuttering of its Gunsan assembly plant on Feb. 12, GM ceased production at a nearby powertrain factory that employed about 100 of the roughly 2,000 employees that it plans to cut as the plant closes, Automotive News has learned.

The powertrain facility produced 2.0-liter diesel engines for the Chevy Captiva, which is built at a plant roughly 100 miles north in Incheon. Engines for the Chevrolet Cruze and Chevrolet Orlando, which the Gunsan plant builds, are being imported from Opel in Europe.

Closing the powertrain plant is expected to have minimal impact on production for GM's Bupyeong operations in Incheon, which produce powertrains and assemble the Captiva, Aveo, Trax and Malibu for Chevrolet. A GM spokesman said the plant has other sources for the engines.

Following the closure, GM also plans to cease operating an "exclusive dock" for shipping less than 1.5 miles away from the plant.

GM expects the closure to cost up to $850 million, including about $475 million in noncash asset writedowns and up to $375 million in primarily employee-related cash expenses. The charges will be substantially recorded in the second quarter, GM said.

The decision to close the facilities came less than a week after GM CEO Mary Barra said company officials were "in discussions" with minority owners and union officials involved with GM Korea that could lead to "some rationalization actions or restructuring."

CEO Mary Barra says GM must take actions "to have a viable business" in South Korea.

"We're going to have to take actions going forward to have a viable business," Barra said during a conference call on Feb. 6 to review the automaker's fourth-quarter and 2017 financial results.

GM said the assembly plant has been increasingly underutilized, running at about 20 percent of capacity over the past three years, "making continued operations unsustainable."

The weak production reflects falling local demand and the loss of a key export market following Chevrolet's 2013 decision to substantially withdraw from Europe.

The closures will bring GM's footprint in Korea down to about 14,000 people; three assembly plants; three powertrain facilities; a large proving ground; and a design studio, in addition to its GM Korea headquarters in Incheon, South Korea.

Workers in Gunsan last week staged a protest against the closure, with the labor union warning of a possible strike if GM doesn't withdraw the plan, Reuters reported.

General Motors says its Gunsan assembly plant has been increasingly underutilized, running at about 20 percent of capacity over the past three years.

GM said it has proposed "a concrete plan to stay in the country and turn the business around" to key stakeholders in the country, including its labor union, the South Korean government and key GM Korea shareholders. The proposal includes significant product-related investments in South Korea and would preserve thousands of jobs, the automaker said.

A GM spokeswoman declined to provide additional details of the turnaround plan.

"This is the first step in a holistic plan to turn GM Korea into an acceptable return on investment," she said in an email. "As the plan progresses, we'll be able to share specific details."

South Korea's government-run development bank owns a 17 percent stake in GM Korea, while GM's main Chinese partner, SAIC Motor Corp., controls 6 percent. GM owns the other 77 percent.

GM Korea, which was established in 2002 with the acquisition of bankrupt Daewoo Motors, employed about 16,000 people in 2017, roughly two-thirds of them hourly workers.

Last year, GM Korea sold about 132,377 vehicles in Korea — down 27 percent from a year earlier — and exported 392,170 vehicles to 120 markets around the world.