Seoul - (AFP) - North Korea warned Tuesday that it would consider any interception of its missiles during tests over the Pacific Ocean as a "clear declaration of war", as confirmed by the sister of North Korean leader Kim Yo Jong , who enjoys wide influence.

"It will be considered a clear declaration of war against the Democratic People's Republic of Korea (DPRK) if a military response takes place such as an interception (of our missiles) during strategic weapons tests," North Korea's official news agency KCNA quoted Kim Yo Jong as saying.

And she warned that "the Pacific does not belong to the United States or Japan," as the United States and South Korea prepare to hold the largest joint military exercises in five years.

She added that North Korea is "always ready to take appropriate, swift and sweeping measures at any time".

The statement comes after Washington and Seoul announced Friday that they will hold the largest joint military exercises since 2018 this month to improve their response to a possible North Korean nuclear attack.

In another statement, the North Korean Foreign Ministry on Tuesday accused the United States of deliberately escalating tensions in the region.

"The recent joint air exercises... clearly show that the US plan to use nuclear weapons against the DPRK is being pushed forward at the level of an actual war," KCNA quoted the ministry as saying.

In addition to the "Ulchi Freedom Shield" maneuvers between the US and South Korean forces, which will begin on March 13 and last at least 10 days, Washington and Seoul this week conducted joint air exercises with the US B-52 strategic heavy bomber.