North Korea's Kim holds security meeting as tensions with Seoul soar

The meeting in Pyongyang was attended by the country's top security officials, including the army chief and other military officials, as well as the ministers of state security and defence.

"He set forth the direction of immediate military action and indicated important tasks to be fulfilled in the operation of the war deterrent and the exercise of the right to self-defence", the Korean Central News Agency (KCNA) reported.

The meeting comes as the nuclear-armed North has accused Seoul of flying drones over its capital and moved troops to its border, with South Korea saying Monday it was "fully ready" to respond if fired upon.

Officials at the meeting in Pyongyang heard a report on the "enemy's serious provocation", KCNA reported, an apparent reference to the drone flights.

Kim "expressed a tough political and military stand" at the meeting, state media said.

The North has accused Seoul of being responsible for the drones, which dropped propaganda leaflets filled with "inflammatory rumours and rubbish", and warned on Sunday that it would consider it "a declaration of war" if another drone was detected.

Seoul's military initially denied it was behind the flights, with local speculation centred on activist groups in the South that have long sent propaganda and US currency northwards, typically by balloon.

The United Nations Command, which oversees the armistice that ended active fighting in the 1950 to 1953 Korean War, said it was aware of the North Korean claim.

"The command is currently investigating the matter in strict accordance with the Armistice Agreement," it said.

The two Koreas remain technically at war.