WASHINGTON (AP) — A cautious President Donald Trump spoke of possible progress Tuesday after South Korea announced that North Korea would halt nuclear weapons and missile tests and put its entire atomic arsenal up for discussion if the U.S. agrees to enter a negotiation. It could also be "false hope," the American leader said.

Trump credited all sides with a "serious effort" as U.S.-allied South Korean envoys returned home from a rare visit to their northern neighbor with the news of an inter-Korean summit planned for late April. But given the North's long history of broken promises on a nucle...