North Korean leader Kim Jong-un has said his country's latest missile tests show it has "the sure capability to attack US interests".
Mr Kim was speaking after twin tests on Wednesday of the Hwasong-10 missile, known internationally as the Musudan.
The US and South Korea say the first test failed, but the second travelled about 400km (250 miles) and reached an altitude of 1,000km.
The UN Security Council expressed its opposition after an emergency meeting.
Alexis Lamek, France's deputy UN ambassador, said all 15 members had "expressed a strong concern as well as their opposition to these launches," Reuters reports.
A spokesman for Secretary General Ban Ki-moon said the tests were "a deliberate and very grave violation" of North Korea's international obligations.
Existing UN resolutions, brought in because of its continuing nuclear and conventional weapons programme, ban North Korea from using ballistic missile technology.
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The Musudan, named by outsiders after a North Korean village, is believed by outside observers to have range of up to 4,000km (2,500 miles).
That is far enough to reach the US territory and military bases in Guam, though it has never been fully flight tested.
Four tests in recent months have ended in failure.