South Korea's National Security Council planned to meet to discuss the latest launch.
North Korea launched two short-range ballistic missiles, two U.S. officials confirmed to NBC News.
The launches were about 15 minutes apart and were thought to be similar to projectiles launched last week, the officials said.
"North Korea fired two unidentified projectiles from Sonduk area in south Hamkyung province in North Korea into the East Sea this morning," South Korea's Joint Chief of Staff's office said Saturday in a text message to NBC News.
South Korea's National Security Council hastily scheduled a meeting Saturday to discuss the launch, said Koh Min Jung, spokesman for President Moon Jae-in.
Japan's Defense Ministry said it did not appear any projectiles had reached Japanese territory.
The last North Korean launch, also including short-range ballistic missiles, took place Aug. 15. The tally of launches since July 31 is now six.
The president said Kim was unhappy with "war games" conducted by South Korea and its allies.
Trump, who has boasted about his friendship with Kim, said on Twitter at the time that he looked forward to meeting again with the North Korean leader to discuss the potential of "a nuclear free North Korea."