Kim ordered the North's nuclear warheads deployed "on standby" in a widely-expected uptick in military sabre-rattling from Pyongyang following the UN Security Council's adoption of tough new sanctions, AFP reported.
"We are following the development of the situation very closely and hope that all the countries in the region and third countries will maintain restraint and equanimity in this difficult situation," Kremlin Spokesman Dmitry Peskov said.
Hours after the United Nations adopted the sanctions, North Korea fired six short-range projectiles into the sea in a new show of defiance.
The latest resolution ushered in the fifth set of UN sanctions on North Korea since it first tested an atomic device in 2006.
The measures are the toughest sanctions to date on North Korea and ban or restrict exports of coal, iron and other minerals from the isolated country, among other restrictions.