North Korea vowed to speed up its nuclear arsenal buildup on Monday, in a message delivered at a U.N. Security Council (UNSC) meeting to discuss its recent launch of a new intercontinental ballistic missile (ICBM).

DPRK Ambassador Kim Song denounced the UNSC session as “unlawful” and stressed that its launch of the Hwasong-19 on Oct. 31 posed no threat to neighboring states.

“We will accelerate and will not let up on [the] build up [of] our nuclear force that can counter any threat presented by hostile nuclear weapon states,” Kim said, adding that “the nuclear threat of the U.S. against