Kim Jong-il, North Korea’s dictator, has immersed himself in high culture for the last few days, directing a Tchaikovsky opera and attending some Chinese musical theatre. But South Korean officials hope he is not building up to a grand finale, trying to upstage their president, Lee Myung-bak, on his visit to Washington.

Before meeting Barack Obama, the US president, Mr Lee on Monday met Hillary Clinton, the US secretary of state, and gained assurances that Washington would not make concessions to Pyongyang, which incurred United Nations sanctions for testing an atomic bomb last month .