Trump, Kim Begin New Phase of Diplomacy

SINGAPORE—President Donald Trump and North Korea’s Kim Jong Un began a high-stakes diplomatic effort to rid the Korean Peninsula of nuclear weapons during their improbable summit here, punctuated by the president’s surprise promise to halt military exercises with South Korea.

With the task ahead to make the agreement concrete, Secretary of State Mike Pompeo is scheduled to travel to Seoul on Wednesday for talks with South Korean and Japanese officials, followed by a trip to China. The decision to cancel the exercises, the…