Olympic organisers have apologised to the North Korean women's football team after their images were shown on a screen beside a South Korean flag.
Kick-off at Glasgow's Hampden Park on the first day of the Games' sporting action was delayed for about an hour.
The venue is hosting two matches later as the men's football competition - which also features Team GB v Senegal at Old Trafford - gets under way.
The penultimate day of the torch relay sees the flame visit Buckingham Palace.
Meanwhile, a crowd of about 60,000 people turned up at Olympic Stadium in Stratford, east London, for the final rehearsal ahead of the Games' opening ceremony on Friday.
Relations between the two Koreas are tense - they remain technically at war following the 1950-53 Korean conflict, which ended in an armistice
The BBC's sports editor David Bond said the incident at Hampden Park was an "embarrassing mistake" and not the start Games organisers would have wanted but "no great harm was done".
As the North Korean players were being introduced before the match against Colombia, South Korean flags were mistakenly displayed in the video package.
The squad walked off and could only be persuaded to return when the teams were announced again with each player's face displayed next to the North Korean flag.
Speaking after the match, North Korea's coach Sin Ui Gun said: "Our team was not going to participate unless the problem was solved properly...
"Unfortunately it took some time later for the broadcast to be done again properly and we made the decision to go on with the match."
It was not immediately clear who had produced the video shown in the stadium.
A statement released by London 2012 organisers said: "We will apologise to the team and the National Olympic Committee and steps will be taken to ensure this does not happen again."
London 2012 spokesman Andy Mitchell said: "The South Korean flag was shown in the video package on the screen before the kick-off and the North Koreans were naturally very upset about that...
"A genuine mistake was made for which we apologise."
On the day before the Olympics opening ceremony, the flame is due to travel between Camden and Hyde Park.
At Buckingham Palace, Princes William and Harry, and the Duchess of Cambridge will greet the flame which will also pass through nearby Downing Street.
Meanwhile, a global investment conference being held in London will kick off a series of business summits organised by the government to showcase the UK and attract investment during the Olympics.
The men's football at Hampden Park gets under way at 1200 BST when Honduras take on Morocco, followed by Spain v Japan.
Matches are also taking place at St James' Park in Newcastle, Cardiff's Millennium Stadium and the City of Coventry Stadium.