The Hwasong-15 missile that North Korea launched on Wednesday is a new type of intercontinental ballistic missile which can fly over 13,000 km (8,080 miles), a South Korean defense ministry spokesman told Reuters on Friday.
Earlier this week, Pyongyang said it had test-fired its most advanced missile, putting the U.S. mainland within range, and in violation of U.N. Security Council resolutions.
The latest provocation from the North prompted more insults from U.S. President Donald Trump, who referred to North Korea's leader Kim Jong Un as "Little Rocket Man" and a "sick puppy".
Trump had also dismissed a Chinese diplomatic effort to rein in North Korea's weapons program as a failure on Thursday, while Secretary of State Rex Tillerson said Beijing was doing a lot, but could do more to limit oil supplies to Pyongyang.
Despite international condemnation and sanctions, North Korea has continued on its path towards developing a nuclear-tipped missile that could hit the United States.
After North Korea released video footage and photographs of Hwasong-15, analysts have said they appeared to show the North was indeed capable of delivering a nuclear weapon anywhere in the United States and could only be two or three tests away from being combat ready.
South Korean President Moon Jae-in said on Thursday in a phone call with Trump that the new missile was North Korea's most advanced so far, but it still has some technical issues to settle, like re-entry and terminal guidance system technology.
Trump and Moon pledged to continue applying strong sanctions and pressure on North Korea to bring it to talks. Addressing an emergency U.N. Security Council meeting after this week's missile launch, the United States warned North Korea's leadership it would be "utterly destroyed" if war were to break out.