South Korean Foreign Minister Cho Hyun is set to travel to the United States on Monday as the fallout continues from an immigration raid on a Hyundai plant in Georgia during which over 300 South Korean workers were detained.

On Sunday, the South Korean government said it had finalized negotiations for the workers' release and planned to send a charter plane to bring them back to Seoul.

But the incident risks seriously damaging relations between the United States and South Korea at a time when Seoul has committed to massive investment plans in America.

Hyundai raid strains US-South Korean relations

Wednesday's raid on the sprawling Hyundai-LG electric vehicle battery factory under construction in Georgia came just ten days after South Korea's new center-left president, Lee Jae Myung, met with US President Donald Trump in Washington, where the two pledged closer business ties.

As recently as July, South Korea agreed to purchase $100 billion (around €85 billion) in US energy and make a $350 billion investment in the US in return for lower tariff rates.

"Launching a massive crackdown while urging 'investment' — is this how you treat an ally?" headlined South Korea's left-leaning Hankyoreh newspaper on Monday, adding: "This incident has left the Korean people feeling betrayed."

Georgia: Why did ICE raid Hyundai plant?

Video footage released by US Immigration and Customs Enforcement (ICE) on Saturday showed a column of vehicles approaching the site in Georgia and then federal agents directing workers to line up outside.

Some detainees were ordered to put their hands up against a bus as they were patted down before having their hands, ankles and waists cuffed.

Steven Schrank, Homeland Security Investigations lead for Georgia, told a news conference that some of the detained workers had illegally crossed the US border. Others, he claimed, had entered the country legally but had expired visas, or had entered on a visa waiver that prohibited them from working.

"It's almost certain they were there on ESTA or B-1 visas, which permit only business meetings, not construction activities," US-licensed attorney Yum Seung-yul told news agency AFP.

None have been officially charged with any crimes, said Schrank, adding that investigations were ongoing — before the announcement on Sunday that the South Korean government would fly the workers home.

Kang Hoon-sik, chief of staff for President Lee Jae Myung, said that Seoul will push to review and improve visa systems for those traveling to the US on business trips or for investment projects.

How could Hyundai raid effect Georgia's economy?

Beyond international relations, the raid could also have a detrimental effect on the local economy, given that the targeted site has been touted as Georgia's largest current economic development project.

It was hoped that the $4.3-billion joint venture between Hyundai and LG Energy Solutions – two leading South Korean firms – would eventually produce batteries for 300,000 electric vehicles per year and generate thousands of local jobs.

LG insisted there had been "no change in our initial timeline for production" but experts say there will inevitably be consequences for South Korean investment in the United States.

"It is also unfavorable for the US, as it suggests that foreign investments and their implementation will be substantially delayed," Kim Yang-hee, professor of economics at South Korea's Daegu University, told the AFP.

"This whole case highlights a considerable gap between principle and reality."

What has President Trump said?

On Sunday, President Trump suggested a potential arrangement by which South Korean workers could train US citizens in battery and computer manufacturing.

"If you don't have people in this country right now that know about batteries, maybe we should help them along and let some people come in and train our people," he told reporters at Andrews Air Force Base.

"The way you train people is to bring people in that know what they're doing, let them stay for a little while and help."

He didn't offer any further details, but wrote on his Truth Social platform: "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."

Edited by: Elizabeth Schumacher