The King has said the UK “stands in solidarity” with the people of South Korea in a message of condolence following the crowd surge that killed more than 150.
Charles said both he and the Queen Consort were “deeply shocked and saddened” by the news of the deaths during during recent Halloween festivities in Seoul.
In his message to the President of South Korea Yoon Suk-yeol, the King said: “I wanted you to know how deeply shocked and saddened both my wife and I are to hear of the many people who have lost their loved ones as a consequence of the recent, tragic incident in Itaewon, Seoul.
“However inadequate this may be under such heartbreaking circumstances, we extend our deepest possible sympathy to all the bereaved families. We also offer our special thoughts and wishes for a speedy recovery to all those who suffered injury.
“Recalling our meeting during your own gracious visit to London to attend the funeral of Her late Majesty The Queen, please be assured that the United Kingdom stands in solidarity with the people of the Republic of Korea at such a time of national mourning.”
President Yoon on Sunday declared a one-week national mourning period and ordered flags at government buildings and public offices to fly at half mast.
The victims, mostly aged in their teens and 20s, were crushed when a huge Halloween party crowd surged into a narrow alley in the Itaewon nightlife district on Saturday night.
Witnesses and survivors have spoken of a “hell-like” chaos with people falling on each other like dominoes.
They said the entire Itaewon area was jammed with slow-moving vehicles and partygoers clad in Halloween costumes, making it impossible for rescuers and ambulances to reach the crammed alleys in time.
Foreign Secretary James Cleverly said he was “saddened by the tragic situation”, while Labour leader Sir Keir Starmer said it was “horrendous news”.
