North Korean leader Kim Jong Un (right) inspects a strategic missile base recently. (Source: KCNA)

The Korean Central News Agency (KCNA) reported that a spokesman for the country's Ministry of Defense announced the " very important test".

The announcement stated that this test launch was conducted under the order of the head of state, updating the latest record of strategic missile capabilities, and demonstrating the modernity and reliability of North Korea's strategic deterrence capabilities.

KCNA quoted North Korean leader Kim Jong Un speaking at the test site as saying that the launch was a completely appropriate military action to demonstrate the will to respond to "those who have recently deliberately aggravated the regional situation and threatened the security of Pyongyang."

The test is also seen as part of an "essential process" to continuously upgrade North Korea's strategic strike force .

According to the leader, it is the "enemy's dangerous moves" such as strengthening the nuclear alliance and "other reckless military activities" that further reinforce the DPRK's efforts to strengthen its nuclear force so as to never allow any threat to approach the country's security perimeter.

Besides, President Kim Jong Un affirmed: "North Korea will never change its policy of strengthening nuclear forces."

The US and Japan have responded to the ICBM launch.

US National Security Council spokesman Sean Savett said the White House considers North Korea's ICBM test a violation of multiple United Nations Security Council (UNSC) resolutions and Washington pledged to take "all necessary measures" to ensure the security of the US, South Korea and Japan.

However, Mr. Savett noted, the US Indo-Pacific Command (INDOPACOM) assessed that this launch did not pose any direct threat to Washington's personnel, territory or allies but "unnecessarily increased tensions and risked destabilizing the security situation in the region".

The US national security team is working closely with allies and partners on the incident, he added.

Meanwhile, Sputnik news agency reported that on the same day, Japanese Chief Cabinet Secretary Hayashi Yoshimasa announced that the country had sent a note of protest to North Korea through diplomatic channels in Beijing.

According to Mr. Hayashi, Japan is conducting an investigation to verify whether any new type of missile was used.

On the South Korean side, President Yoon Suk Yeol has "ordered a strong response" to North Korea's actions together with the international community and is fully prepared to respond to similar moves from Pyongyang.

South Korea will impose new sanctions on North Korea in response to the ICBM launch, the South Korean presidential office said.