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Plane will get workers when administrative work done,

Seoul says

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Trump's border czar says more businesses will be targeted

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Seoul dismayed but says it will examine visa issues

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Hyundai workers could return on Wednesday, Yonhap reports

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Trump says foreign companies need to train Americans

By Cynthia Kim and Jeff Mason

SEOUL/WASHINGTON, Sept 7 (Reuters) - South Korea is

moving to pick up Korean workers following a raid at a Hyundai

Motor ( HYMLF ) manufacturing facility in the U.S. state of

Georgia last week, a Korean presidential official said on Sunday

as the Trump administration promised more raids on businesses.

The negotiations to release about 300 South Koreans who were

detained have concluded and processing for their release from

custody is ongoing, South Korea's presidential office said late

on Sunday.

A chartered plane will be flown to bring them back as soon

as the processing by the two countries is complete, the office

said in a statement. It did not provide details of what

administrative steps are being taken.

The Yonhap news agency quoted South Korean Consul General in

Washington Cho Ki-joong as saying the workers will likely board

a plane on Wednesday.

Representatives for the Department of Homeland Security did not

respond to a request for comment, while White House border czar

Tom Homan separately vowed to expand immigration raids on

workplaces.

Later on Sunday, U.S. President Donald Trump sounded more

conciliatory while still driving home a vow to enforce tough

immigration policy, calling on foreign companies investing in

the U.S. to "respect our Nation's immigration laws."

"Your Investments are welcome, and we encourage you to

LEGALLY bring your very smart people, with great technical

talent, to build World Class products, and we will make it

quickly and legally possible for you to do so," he said on his

social media platform.

Trump made the post shortly after telling reporters he

would look at what happened but that the incident had not harmed

his relationship with South Korea.

U.S. federal agents arrested about 475 workers at Hyundai's

car battery plant in Ellabell, Georgia, on Thursday in the

largest single-site enforcement operation in the history of the

Department of Homeland Security's investigative operations.

Trump campaigned on making immigration a pillar of his

administration and has moved to ramp up deportations nationwide

since taking office in January. He has also buttressed his

economic plan in large part on wooing other countries and

foreign businesses to invest in the United States.

The roundup of 475 workers including about 300 South Korean

workers at the major Hyundai Motor ( HYMLF ) car battery plant under

construction caused shock and dismay in Seoul, as it came just

10 days after a summit between the U.S. and South Korean

presidents where they pledged closer business ties.

South Korea's government expressed regret about the arrests and

the public release of the footage showing a major operation by

U.S. immigration authorities involving armoured vehicles

detaining the workers who were shackled and taken in.

The DHS earlier said the operation was executed under a

judicial search warrant over alleged unlawful employment

practices. A customs official has said many of those arrested

did not have proper immigration authorization to work at the

site.

AUTOS BIG PART OF SOUTH KOREAN INVESTMENT IN U.S.

South Korea's presidential chief of staff, Kang Hoon-sik, said

on Sunday the government will seek ways to improve the visa

system of Korean workers traveling to the U.S. to "prevent a

similar incident."

DHS has said the arrested workers were barred from working

in the U.S. after crossing the border illegally or overstaying

visas.

Relations remain fraught between Washington and Seoul, a key

U.S. ally and investor, as both sides seek to hammer out final

details of their trade deal announced in July.

The trade deal includes a $350 billion fund to help Korean

companies enter the U.S. market, while Hyundai said it was

boosting its U.S. investments to $26 billion, including a

U.S.-based robotics facility.

The site of the raid was a $4.3 billion project to produce

EV batteries, with Hyundai and LG Energy Solution

each holding a 50% stake as part of one of the largest economic

development projects in Georgia's history.

LG Energy Solution has suspended staff business trips to the

United States other than certain exceptional cases and will be

recalling those employees now in the United States.

Trump may visit South Korea in October for the gathering of

the Asia-Pacific Economic Cooperation event, Reuters has

reported, citing sources.