North Korea has emphasized the "life and death" importance of its defensive nuclear prowess in repelling enemy threats against the country.

“This is a matter of life and death for us. The current situation deepens our understanding that we need nuclear weapons to repel a potential attack,” Choe Son-hui, the director-general of the North American department of North Korea’s Foreign Ministry, said on Friday.

The high-ranking diplomat, who was speaking at a non-proliferation conference in the Russian capital, Moscow, said North Korea had been under perpetual military threat by the United States for decades.

North Korea - officially known as the Democratic People's Republic of Korea (DPRK) - is "under the constant nuclear threat by the United States and as early as last week there was unprecedented military exercises involving aircraft carriers in addition to the flying exercises by the nuclear strategic bombers into the Korean Peninsula,” she said, adding that every action had a reaction. “We will respond to fire with fire.”

The North Korean official said to reach a peaceful solution to the Korea crisis through negotiations, the US and its regional allies must quit hostile behaviors. “We will never put our nuclear weapons and ballistic rockets on the table of negotiations in any case, unless the United States puts an end to its hostile policy and nuclear threat on the DPRK.”

She said Pyongyang's goal is to achieve a “power balance” with the US so that there will be no more talk of military actions against the DPRK.

“Today we have almost reached the final stage of balance of power with the United States and our ultimate goal is to achieve a power balance with the United States so that the United States will not dare to talk about any military actions against the DPRK, “ she said.

In response to US President Donald Trump's derogatory remarks against North Korean leader Kim Jong-un, Choe said the North Korean head of state would "tame the mentally-deranged US dotard with fire."

She concluded her remarks by reminding that the US must take North Korea's concerns and position "seriously."

North Korea is under mounting international pressure over its missile and military nuclear programs and has been subjected to an array of sanctions by the United Nations. However, Pyongyang says it needs to continue and develop the programs as a deterrent against hostility by the US and its regional allies, including South Korea and Japan.