SEOUL (Reuters) - North Korea said on Tuesday it will scrap the armistice signed in 1953 that ended a three-year conflict with rival South Korea if the South and the United States continue with two-month long annual military drills.

The threat was attributed by the KCNA news agency to the Korean People's Army Supreme Command spokesman and raises the level of bellicose rhetoric from the North, which faces additional international sanctions after its nuclear test last month.

It has already warned of "destruction" of the South if it goes ahead with the military exercises with the United States.

The two Koreas are still technically still at war after the 1950-53 civil war ended in a truce rather than a treaty.

(Reporting by Jack Kim; Editing by Nick Macfie)