Washington, 25 Aug

US President Donald Trump greeted Lee Jae Myung, the new president of South Korea, by asserting that a “Purge or Revolution" was taking place there and threatening to not do business with Seoul as he prepared to host the new leader at the White House later Monday.

It was not immediately clear what Trump was referring to, but South Korea had been in a state of political turmoil for the last several months after its former leader, the conservative Yoon Suk Yeol, briefly imposed martial law last December, which eventually led to his stunning ouster from office.

“WHAT IS GOING ON IN SOUTH KOREA? Seems like a Purge or Revolution. We can't have that and do business there," Trump posted on social media Monday morning. "I am seeing the new President today at the White House. Thank you for your attention to this matter!!!”

Yoon, who was elected to a five-year term in 2022, was considered more ideologically aligned with Trump and had even taken up golfing again after the US president was re-elected last November to try to forge a bond with him.

The liberal Lee, an outspoken critic of Seoul's conservative establishment who had narrowly lost to Yoon in that 2022 election, led the South Korean parliament's efforts to overturn Yoon's martial law decree while impeaching him. The nation's Constitutional Court formally dismissed Yoon in April.

Before Trump's Truth Social post Monday morning, the first in-person meeting between Trump and Lee had been expected to help flesh out details of a July trade deal between the two countries that has Seoul investing hundreds of billions of dollars in the US. The agreement set tariffs on South Korean goods at 15 per cent after Trump threatened rates as high as 25 per cent.

Trump declared at the time that South Korea would be “completely OPEN TO TRADE” with the US and accept goods such as cars and agricultural products. Automobiles are South Korea's top export to the US.

Seoul has one of the largest trade surpluses among Washington's NATO and Indo-Pacific allies, and countries where the US holds a trade deficit has drawn particular ire from Trump, who wants to eliminate such trade imbalances.

Lee's office said in announcing the visit that the two leaders plan to discuss cooperating on key manufacturing sectors such as semiconductors, batteries and shipbuilding. The latter has been a particular area of focus for the US president.

On defence, one potential topic is the continued presence of US troops in South Korea and concerns in Seoul that the US will seek higher payments in return.

Ahead of his visit to Washington, Lee travelled to Tokyo for his first bilateral visit as president in a hugely symbolic trip for the two nations that hold longstanding historical wounds.

The summit with Japanese Prime Minister Shigeru Ishiba was interpreted by analysts as a way to show unity and potential leverage as Japan and South Korea face new challenges from the Trump administration.

Lee was the first South Korean president to choose Japan for the inaugural bilateral visit since the two nations normalized ties in 1965.

Elected in June, Lee was a former child labourer with an arm deformity who rose his way through South Korea's political ranks to lead the liberal Democratic Party and win the presidency after multiple attempts.

Lee faced an assassination attempt in January 2024, when he was stabbed in the neck by a man saying he wanted Lee's autograph and later told investigators that he intended to kill the politician.

Lee arrived in the US on Sunday and will leave Tuesday. He headlined a dinner Sunday evening with roughly 200 local Korean-Americans in downtown Washington on Sunday night.