In another sign of the King's K-pop diplomacy, the members of South Korean girl group Blackpink have been presented with honorary MBEs.
It comes during the state visit by South Korea President Yoon Suk Yeol, in which King Charles had praised the global reach of Korean pop culture.
Blackpink were name-checked by the King for supporting environmental causes.
"I can only admire how they can prioritise these vital issues, as well as being global superstars," he said.
The MBEs recognise how the girl group acted as ambassadors for the COP climate change summit and have been advocates for the UN's sustainable development goals, helping to bring the environmental message to "millions of young people".
There was a special investiture this morning in the 1844 room in Buckingham Palace, often used for the most distinguished guests.
It was another reflection of the red carpet being rolled out during this South Korean state visit, with the diplomatic courtship reflecting the increasing importance of this strategic ally and economic partner.
The members of Blackpink - Roseanne Park, Jennie Kim, Jisoo Kim and Lalisa Manoban - are now honorary members of the Order of the British Empire and were guests at the state banquet in Buckingham Palace on Tuesday evening.
The King's speech had highlighted the global reach of South Korean popular culture and its "remarkable ability to captivate imaginations".
While the King admitted to a personal lack of "what might be called Gangnam Style", the military band for the changing of the guard put that right on Wednesday morning, by playing the song in a surprise change of musical direction.
Tourists gathered outside Buckingham Palace to watch changing of the guard had heard an unexpected medley of K-pop songs, rather than marching tunes.
There had been a full ceremonial welcome for South Korean President Yoon Suk Yeol on Tuesday - greeted by the King, Queen and the Prince and Princess of Wales, before taking part in a carriage procession along the Mall.
In the evening, the president was given the grand spectacle of a state banquet, held in the Buckingham Palace ballroom, with 170 guests including the Prime Minister Rishi Sunak and Foreign Secretary Lord Cameron as well the Royal Family and South Korean dignitaries.
State visits are a mix of serious diplomacy as well as pageantry - and the focus of the South Korean visit is on boosting trade links and military partnerships.
South Korea's President Yoon is meeting Mr Sunak to sign a "Downing Street Accord", with plans for a new trade deal, with technology and green energy likely to be areas of co-operation.
There are plans for a stronger approach to enforcing sanctions against North Korea, and preventing its "illegal weapons programme", with joint sea patrols between the South Korean navy and the UK's Royal Navy.
"Long term, global partnerships are vital to our prosperity and security," Mr Sunak said.
