North Korea's defence ministry said on Saturday that "military provocations" by the United States and its allies were becoming more "pronounced" under the current Trump administration, according to state media.

In a statement carried by KCNA, the information office chief at the ministry, who was not named, said Washington and its "vassal forces" were threatening the security environment of the DPRK (Democratic People's Republic of Korea), referring to recent joint military drills and US military presence in South Korea.

"We will counter the enemies' strategic threat with our strategic means," the official added while vowing that Pyongyang will continue its military activities. South Korea's defence ministry said on Thursday that a joint air drill was held with the US with at least one B-1B strategic bomber taking part.

North Korea has long condemned such military drills as rehearsals for war, while Seoul has portrayed the exercises as purely defensive.