South Korea and the United States have fired a "barrage of missiles" along the eastern coast of the Korean Peninsula, a day after North Korea said it conducted its first successful intercontinental ballistic missile (ICBM) test.
North Korea said it carried out the ICBM tests on Tuesday under the supervision of leader Kim Jong-un, and that it was capable of hitting anywhere in the world.
The Hwasong-14 missile reached an altitude of 2,802km and hit its target precisely after flying for 39 minutes, the North's state television said.
In response, "deep strike" precision missiles were fired into the South Korean territorial waters on Wednesday to show North Korea a "firm combined missile response posture", South Korean President Moon Jae-in's office said.
US General Vincent Brooks, the Combined Forces commander in South Korea, said: "Self-restraint, which is a choice, is all that separates armistice and war.
"As this alliance missile live fire shows, we are able to change our choice when so ordered by our alliance national leaders."
But the US-South Korean drills will "probably not" have an effect on North Korea, Robert Kelly, a professor of Pusan National University, told Al Jazeera.
"The North Koreans have said for a long time that they want to develop a nuclear weapon and missile and marry the two. They've said for a long time that they want the ability to strike the continental United States," said Kelly.
"[The drills are] probably more of just a show of force, a sort of tit-for-tat ... but will probably not dissuade the North Koreans from continuing to push towards a longer range missile."
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The North Korean leader also vowed to never abandon nuclear weapons and to keep sending Washington more "gift packages" of missile and atomic tests, according to the North's official Korean Central News Agency.
Following Tuesday's test, worry spread in Washington and at the United Nations, where the US, Japan and South Korea requested a UN Security Council emergency session, to be held later Wednesday.
US Secretary of State Rex Tillerson said the US response would include "stronger measures to hold the DPRK accountable", using an acronym for the nation's formal name, the Democratic People's Republic of Korea.
The test, North Korea's most successful yet, is a direct rebuke to President Donald Trump's earlier declaration that such a test "won't happen".
Soon after Tuesday's launch, Trump responded on Twitter: "North Korea has just launched another missile. Does this guy have anything better to do with his life? Hard to believe that South Korea and Japan will put up with this much longer. Perhaps China will put a heavy move on North Korea and end this nonsense once and for all".
'Unacceptable'
Meanwhile, Russia and China called for a simultaneous freeze on North Korean nuclear and missile tests as well as military exercises by the US and South Korea.
The positions were announced in a joint document issued after a meeting between leaders Vladimir Putin and Xi Jinping in the Russian capital of Moscow on Tuesday, in which they also condemned Pyongyang's latest missile test as "unacceptable" and urged against "any statements or actions that could lead to an increase in tensions".
Russia and China have the closest diplomatic relations with the insular nation of North Korea.
