Top South Korean, U.S. and Japanese military officers urged North Korea to cease all unlawful activities that threaten regional security, as the three nations flew advanced warplanes for a joint exercise in a show of force against the North.

Russia's foreign minister on Saturday warned the U.S., South Korea and Japan against forming a security partnership targeting North Korea as he visited his country's ally for talks on further solidifying their booming military and other cooperation.

Japan-South Korean alliances during his meeting with Kim Jong Un, highlighting the "invincible fighting brotherhood" with the country.