North Korea threatened the U.S. Pacific territory of Guam on Tuesday night, Reuters reported.

The threat came hours after President Donald Trump said he would respond with "fire and fury" if North Korea does not cease its threats against the U.S.

Pyongyang said it is "carefully examining" a plan to strike Guam with missiles, according to Reuters, which cited a statement by a spokesman for the Korean People's Army which was carried by the North's state-run KCNA news agency.

The spokesman said the strike plan will be "put into practice in a multi-current and consecutive way any moment" once North Korean leader Kim Jong Un makes a decision.

In another statement citing a different military spokesman, North Korea also said it could carry out a pre-emptive operation if the United States showed signs of provocation.

Trump’s remarks followed reports that North Korea has produced a nuclear warhead small enough to fit onto an intercontinental ballistic missile (ICBM), which could strike parts of the U.S.

Last month, a top American general warned that North Korea "clearly" had the capability to strike parts of the U.S. with an ICBM. The rogue nation has repeatedly test-fired ballistic missiles recently.

Late last week, the UN Security Council voted to place new sanctions on North Korea in response to its recent missile tests.

The U.S.-drafted resolution imposes a ban on exports aimed at depriving Pyongyang of $1 billion in annual revenue. It also imposes a full ban on exports of coal, iron and iron ore, lead and lead ore as well as fish and seafood by North Korea.

North Korea vowed in response to bolster its nuclear arsenal and gain revenge of a "thousand-fold" against the United States.