The intercontinental ballistic missile (ICBM) launch snapped a two-month pause in testing by the North. The state television brought out Ri Chun-Hee, a star presenter who only appears for significant developments, to announce the landmark, AFP reported.
"The great success in the test-fire of ICBM Hwasong-15 is a priceless victory won by the great and heroic people of the DPRK," she said, using the official abbreviated name for North Korea.
Wednesday's missile was more sophisticated than any previously tested, state media said.
“The ICBM Hwasong-15 type weaponry system is an intercontinental ballistic rocket tipped with a super-large heavy warhead which is capable of striking the whole mainland of the US,” the North’s official news agency KCNA said.
Pyongyang said the missile reached an altitude of 4,475 kilometers (2,800 miles) and splashed down 950 kilometers from its launch site.
At least one Western expert said the missile’s lofted trajectory suggested an actual range of 13,000 kilometers – enough to hit every major US city.
US President Donald Trump, who recently announced fresh sanctions on Pyongyang and returned it to a US list of state sponsors of terror, was opaque in his immediate response, as the UN Security Council agreed to meet in an emergency session.
“I will only tell you that we will take care of it,” Trump said at the White House. “It is a situation that we will handle,” he added, without elaborating.
Russia called the launch "provocative," and China, North Korea's sole major ally and diplomatic protector expressed "grave concern and opposition."
Beijing once again pressed its proposal that the North stop missile and nuclear tests in exchange for a freeze of US military exercises.
Washington has repeatedly rejected the suggestion.
The launch was the North's third successful ICBM test.
Wednesday’s statement from the North stressed the notion it had become a full-fledged nuclear power and offered language redolent of a "no first strike" doctrine.
Its weapons "would not pose any threat to any country and region as long as the interests of the DPRK are not infringed upon. This is our solemn declaration," state media said.
Tensions over the North's weapons program peaked after Pyongyang conducted its sixth and most powerful nuclear test in September and then fired an intermediate-range missile over Japan.
The Trump administration last week unveiled new sanctions targeting North Korean shipping, as well a number of Chinese companies doing business with the pariah state.