North Korea paraded new missiles during a military celebration in honor of the 105th birthday of its founder, Kim Il Sung.
Kim Jong-un oversaw the festivities on the "Day of the Sun" at Pyongyang's main Kim Il Sung Square.
State television showed Kim, wearing a black suit and white shirt, stepping out of a limousine and saluting his honour guard before walking down a red carpet.
Pyongyang has also expressed anger over the ongoing annual spring military exercises the US holds with South Korea, which it considers a rehearsal for invasion.
The North has said it has developed and would launch a missile that can strike the mainland United States, but officials and experts believe such a threat is some time away.
China, on the other hand, acts as an economic bedrock for North Korea.
During a speech at the parade, a high-ranking North Korean official blamed the Trump administration for heightened tensions on the Korean peninsula, saying North Korea will respond with "all-out war and a nuclear war" if attacked. The country conducted two nuclear tests a year ago.
The North launched a ballistic missile from the same region earlier this month ahead of a summit meeting between the leaders of the United States and China, its key ally, to discuss the North's increasingly defiant arms programme.
The Pukkuksong submarine-launched ballistic missiles were also on parade.More news: Kier Group plc's (KIE) "Buy" Rating Reaffirmed at Berenberg Bank
"If they infringe on the DPRK's sovereignty and dignity even a bit, its army will launch merciless ultra-precision strikes from ground, air, sea and underwater", North Korea said through its state-run news source.
North Korean soldiers are facing the death penalty after spreading a joke comparing Kim Jong-un to a kindergartner.
Following the huge bomb dropped by the U.S. in Afghanistan, China's Global Times - the Communist Party's official newspaper - said North Korea must have felt the shockwaves.
DPRK has promised to give a fit reply to any provocation by the United States, saying it is capable of hitting targets on USA soil.
North Korea's leadership has warned the U.S. it is "ready to hit back with nuclear attacks" if provoked.
And on the same day, a top North Korean official offered a warning to the US, accusing President Trump of "creating a war situation".
Speaking in Beijing yesterday, China's foreign minister Wang Yi warned the region is facing a "precarious situation" and that a conflict could break out "at any moment".
Speculation has been intensifying that U.S. President Donald Trump might order a pre-emptive strike on North Korea if it shows imminent signs of a significant provocation such as a sixth ever nuclear test.
"If they attempt a full-scale war, we will respond with a full-scale war", Choe Ryong Hae, a senior official in the ruling Workers' Party and a key aide to Kim, said in a speech before the parade, the Times reported.