“They haven’t been able to get a bill through to do the investment, they’ve introduced new laws on digital services, they haven’t done what they needed to do on agriculture and industry. And so it’s hard to continue to hold up our end of the bargain while they have not moved forward swiftly enough on their end,” Greer said Tuesday in a Fox Business interview.

The episode illustrates how Trump continues to sow trade uncertainty as his term stretches into its second year. He has recently threatened new levies against products from Europe, Canada and nations doing business with Iran — measures that if implemented could undercut deals he brokered last year. The Supreme Court’s upcoming ruling in a case over his global tariffs could also come in the next month.

On Tuesday, Trump suggested the US and South Korea could swiftly resolve the dispute, telling reporters: “We’ll work something out. We’ll work something out with South Korea.”

Trump on Monday declared his intent to hike US levies on goods from South Korea to 25% from the 15% current rate. While the president’s announcement on social media implied the new rate was already in place, the administration has not yet moved to implement it.

South Korea is the latest nation to be singled out by Trump administration officials over moving too slowly to fulfill trade promises. Greer has criticized what he’s cast as slow progress by the European Union. Indonesia also has drawn fire for the pace of its pledged trade commitments. US officials, however, have contrasted South Korea’s speed with that of Japan, which is seen as moving more expeditiously to deliver on its pact, a White House official said.

A domestic bill was introduced in South Korea last November to codify its investment commitments under the trade deal, but progress on passing it has been slow over uncertainty regarding capital outflows, currency volatility and the process of selecting projects.

US officials have also harbored longstanding concerns about South Korea’s rules discriminating against leading American digital platforms and related service providers, but those aren’t pertinent to Trump’s tariff announcement, a White House official said.

Trump and his aides have railed against digital-services taxes and regulations in the EU and Canada. Scrutiny of South Korea has intensified in recent days, as US investors raise complaints — and seek a federal trade investigation — over Seoul’s probe of a high-profile data breach at Coupang.

In a meeting with US lawmakers last week, South Korea’s Kim insisted his government wasn’t discriminating against Coupang.

The firm disclosed a data breach in November that affected roughly two-thirds of South Korea’s population. In the aftermath, a major shareholder, Greenoaks Capital Partners LLC, filed a petition asking the Office of the US Trade Representative to open a trade probe into South Korea. Separately, South Korea’s Justice Ministry has said US-based shareholders of Coupang, including Greenoaks and Altimeter Capital Management LP, have submitted a notice of intent under the Korea–US free trade agreement.

Concerns about the treatment of US digital-service providers persist regardless of the ongoing Coupang case, the White House official added.

Many of Trump’s second-term tariff threats ultimately have been scaled back or reversed. Data compiled by Bloomberg show that about 27% of such threats since late 2024 were fully executed.

Yet if the US implements Trump’s announced 25% tariffs on South Korea, it could have wide-ranging consequences on major companies that export to the US, including Hyundai Motor Co., which sent 1.1 million vehicles to America in 2024.

–With assistance from Kate Sullivan, Heesu Lee and Brian Fowler.

(Updates with South Korea’s trade ministry comment.)

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