The United States flew two B-1B bombers over the Korean peninsula in a show of force after recent North Korean missile tests, the US air force said on Sunday.
North Korea said it conducted another successful test of an intercontinental ballistic missile (ICBM) on Friday that proved its ability to strike America's mainland, drawing a sharp warning from US president Donald Trump.
The B-1B flight was in direct response to the missile test and the previous July 3 launch of the Hwansong-14 rocket, the US air force said. The bombers took off from a US air base in Guam, and were joined by Japanese and South Korean fighter jets during the exercise.
The South Korean air force said the flight was conducted early on Sunday.
The commander of America's Pacific air forces , General Terrence J O'Shaughnessy, said: "North Korea remains the most urgent threat to regional stability. If called upon, we are ready to respond with rapid, lethal, and overwhelming force at a time and place of our choosing."
The US has used overflights of the supersonic B1-B "Lancer" bomber as a show of force in response to previous North Korean missile or nuclear tests.
North Korean leader Kim Jong-un personally supervised the midnight test launch of the missile on Friday night and said it was a "stern warning" for the United States that it would not be safe from destruction if it tries to attack, the North's official KCNA news agency said.
North Korea's state television broadcast pictures of the launch, showing the missile lifting off in a fiery blast in darkness and Mr Kim cheering with military aides.
China, the North's main ally, said it opposed North Korea's missile launches, which violate United Nations Security Council resolutions designed to curb Pyongyang's banned nuclear and missile programmes.
"At the same time, China hopes all parties act with caution, to prevent tensions from continuing to escalate," the foreign ministry said.
However, Mr Trump said he was "very disappointed in China".
In a message on Twitter, he said: "Our foolish past leaders have allowed them to make hundreds of billions of dollars a year in trade, yet they do NOTHING for us with North Korea, just talk. We will no longer allow this to continue. China could easily solve this problem!"
The Hwasong-14, named after the Korean word for Mars, reached an altitude of 3,724.9 kilometres and flew 998km for 47 minutes and 12 seconds before landing in the waters off the Korean peninsula's east coast, KCNA said.
Western experts said calculations based on that flight data and estimates from the US, Japanese and South Korean militaries showed the missile could have been capable of reaching inland US cities such as Denver and Chicago.
David Wright of the US-based Union of Concerned Scientists wrote in a blog post that if it had flown on a standard trajectory, the missile would have had a range of 10,400km.
North Korea refers to the United States as its sworn enemy in its propaganda, and has done so since the 1950-53 Korean War in which the Soviet and Chinese-backed North fought against the US-backed South. The isolated country often shows mockup images of a missile hitting key US landmarks in its media.
