By Mark Landler and Choe Sang-Hun
WASHINGTON — North Korea threw President Trump’s planned summit meeting with its leader, Kim Jong-un, into doubt on Tuesday, threatening to call off the landmark encounter to protest a joint military exercise of the United States and South Korea.
The warning, delivered early Wednesday in North Korea via its official government news agency, caught Trump administration officials off guard and set off an internal debate over whether Mr. Kim was merely posturing in advance of the meeting in Singapore next month or was erecting a serious new hurdle.
North Korea had previously signaled flexibility about the military exercises, appearing to remove a perennial obstacle to talks between North and South Korea. But the North also cited its objections to the joint American-South Korean air force drill in postponing a separate high-level meeting with South Korea that had been planned for Wednesday.
