North Korea has threatened "indiscriminate" nuclear strikes, including on the United States and South Korea, over the two nations' joint military exercises.
The new threat comes days after leader Kim Jung Un ordered the country's nuclear weapons be readied for use "at any time".
In a statement on the official Korean Central News Agency (KCNA), Pyongang says the US/South Korean military exercises set to start today are a pretext for war, and that tensions on the peninsula had been brought to a boil by last week's United Nations sanctions.
"If the enemies dare kick off even the slightest military action while vociferating about 'beheading operation' aimed to remove the supreme headquarters of [North Korea] and 'bring down its social system', its army and people will not miss the opportunity but realise the greatest desire of the Korean nation through a sacred war of justice for reunification," reads the KCNA dispatch of the military statement.
"If we push the buttons to annihilate the enemies even right now, all bases of provocations will be reduced to seas in flames and ashes in a moment and the US imperialists' nuclear strategic means on which the puppet forces depend as 'saviours' turn into piles of scrap iron whether they are in the air, seas and land."
Pyongyang has long condemned the drills as provocative rehearsals for invasion of the North, while Seoul and Washington insist they are entirely defensive.