UN Secretary-General Ban Ki-moon has warned the crisis on the Korean peninsula may become "uncontrollable".
Speaking to reporters in Rome, the UN chief urged North Korea to refrain from further raising tensions.
He once again called upon North Korea to tone down its "provocative rhetoric" and to keep open the joint North-South Korean Kaesong industrial complex.
“"Pyongyang authorities should look at what is happening, what is going on around the world in this era of globalization," Ban said, adding that North Korean authorities “should do more enhance the well-being and prosperity of their own people rather than increasing level of tensions."
Last week, North Korea asked foreign embassies based in Pyongyang to consider evacuating staff.
Pyongyang issued on Tuesday a warning to foreigners in South Korea, saying they should take steps to secure shelter or evacuation to protect themselves in the event of a conflict on the Korean Peninsula