DPRK warned it would be a "clear declaration of war" if its missiles were shot down during test launches over the Pacific Ocean.

This comes shortly after the US flexed its muscles, provoking DPRK with B-52 in a joint drill with South Korea.

DPRK has reiterated that its nuclear and missile programs are for self-defense and was enraged with the US-South Korean military exercises, portraying them as drills for an invasion.

"It will be regarded as a clear declaration of war against the DPRK, in case such military response as interception takes place against our tests of strategic weapons," Kim Yo Jong, DPRK's leader Kim Jong Un's sister, said in a statement.

"The Pacific Ocean does not belong to the dominium of the US or Japan," she stated.

DPRK is "always on standby to take appropriate, quick and overwhelming action at any time", added her statement, as quoted by the official Korean Central News Agency (KCNA).

South Korea's Defense Ministry said on Monday that the United States deployed a B-52 bomber for a joint drill with its ally South Korea. The move is considered a fresh military provocation, further destabilizing the regional security of East Asia.

The air drill comes ahead of a large-scale joint exercise, which will reportedly include an amphibious landing later this month. DPRK has routinely urged for the cancellation of joint drills, characterizing them as a precursor to invasion.

This comes in light of a recent announcement made by the US and South Korea that the two are planning to carry out joint military drills, dubbed the "Freedom Shield" exercises, this month in order to strengthen allies' "defense" capabilities. 

The drills are scheduled to take place annually from March 13 to March 23. No breaks are scheduled to be held in between. 

That will also mark the longest-ever version of a joint computer simulation command post-exercise.