The missile appears to have travelled higher and further than any previous ICBM tested by the nuclear-armed country -- including one designed to strike anywhere on the US mainland.
At the UN Security Council on Friday, the United States said the recent launches were "increasingly dangerous provocations", and called for a "resolution to update and strengthen the sanctions regime" against Pyongyang.
The move would follow up on sanctions implemented after the North's last test in 2017, when the council promised further measures in the event of future launches, US Ambassador to the United Nations Linda Thomas-Greenfield said.
"This is precisely what happened. So now is the time to take that action," she added.
However, China urged "prudence and reason".
"All is not quiet on the international front," China's UN ambassador Zhang Jun said. "No parties should take any action that would lead to greater tensions."
Russia warned against following Washington's lead on tightening sanctions, saying it believed doing so would "go beyond the framework of cutting off financing" for the DPRK missile and nuclear programmes and would "threaten North Korean citizens with unacceptable socio-economic and humanitarian problems".
Following the meeting, a group of 15 nations including permanent Security Council members Britain, France and the US -- but minus China and Russia -- released a joint statement urging UN member states, in particular UNSC members, to do more.
"The DPRK is demonstrating its determination to continue advancing its weapons programme as it escalates its provocative behaviour -- and yet the Council has remained silent," said the statement, which included non-permanent Security Council members Brazil, Ireland and Norway, as well as Germany, Japan and South Korea.
Known as the Hwasong-17, the giant ICBM launched Thursday was first unveiled in October 2020 and dubbed a "monster missile" by analysts.
It had never previously been successfully test-fired.
North Korean state media photographs showed Kim, wearing his customary black leather jacket and dark sunglasses, striding across the tarmac in front of a huge missile, with other images of him cheering and celebrating the test launch with uniformed military top brass.
South Korea's military had estimated the range of the Thursday launch as 6,200 kilometres (3,900 miles) -- far longer than the last ICBM, the Hwasong-15, which North Korea tested in November 2017.
The missile landed in Japan's exclusive economic zone, prompting anger from Tokyo, but KCNA said the test had been carried out "in a vertical launch mode" to ease neighbours' security concerns.
Following the test, Washington imposed new sanctions on entities and people in Russia and North Korea who are accused of "transferring sensitive items to North Korea's missile programme".
The test is a clear sign North Korea has made "important qualitative progress" on its banned weapons programmes, said US-based analyst Ankit Panda.
"What's important about this ICBM is not how far it can go, but what it can potentially carry, which is multiple warheads," he told AFP.
Multiple warheads would help a North Korean missile evade US missile defence systems.
"The North Koreans are on the cusp of significantly increasing the threat to the United States beyond the ICBM capability demonstrated in 2017," Panda added.
Long-range and nuclear tests were paused when Kim and then US president Donald Trump engaged in a bout of diplomacy which collapsed in 2019. Talks have since stalled.
Thursday's launch, one of nearly a dozen North Korean weapons tests this year, marked a dramatic return to long-range testing.
It came just days after one last week, likely also of the Hwasong-17, failed, exploding after launch.
"This test also appears to 'compensate' for last week's failed projectile launch -- handsomely so," Soo Kim, RAND Corporation Policy Analyst and former CIA analyst, told AFP.
The launch comes at a delicate time for the region, with South Korea going through a presidential transition until May, and the US distracted by Russia's invasion of Ukraine