Donald Trump has said military solutions for North Korea are "locked and loaded", amid escalating tensions over nuclear weapons.
His tweet comes after several days of strident rhetoric from both sides, including a spontaneous statement by Mr Trump that Pyongyang faced "fire and fury like the world has never seen" if it continued to threaten the US.
Mr Trump said on Friday: "Military solutions are now fully in place,locked and loaded,should North Korea act unwisely. Hopefully Kim Jong Un will find another path!"
The President did not specify whether the solutions were preemptive or reactive.
His tweet attracted immediate criticism from opponents.
Ben Rhodes, a former foreign policy adviser to Barack Obama, said: "This isn't a video game. Hundreds of thousands of lives at stake in war with NK. Was this statement signed off on by anyone?
"Was this statement coordinated with South Korea and Japan, our allies who are at enormous risk in conventional conflict with North Korea?"