US President Barack Obama has said that North Korea violated international rules when it tested a rocket capable of sending weapons at long range, and called on the UN Security Council to take action, a media report said.
"This provocation underscores the need for action, not just this (Sunday) afternoon at the Security Council but in our determination to prevent the spread of these weapons," Obama said.
"Rules must be binding. Violations must be punished. Words must mean something," the New York Times quoted Obama as saying on Sunday.
The US Northern Command issued a statement that North Korea's Taepodong 2 missile flew over Japan, with its payload landing in the Pacific Ocean.
"No object entered orbit and no debris fell on Japan," the assessment said.
White House officials said the failure of the launch would not stop the US from taking the matter to the Security Council.
"I think there have been a number of instances now where the North Koreans have failed in these attempts," White House Spokesman Robert Gibbs said.
"The launch itself was a violation," he said, adding that the fact that the launch failed did not make a difference in pursuing punitive sanctions.
Obama's comments on North Korea were delivered in Prague at the end of a historic speech before more than 20,000 people that, in a twist of irony, was planned in advance to lay out Obama's plans to stop the spread of nuclear arms.
Deliberate or not, the North Korean action served the dual purpose of lending urgency to Obama's speech while emphasising the often tied hands of the international community with regard to stopping North Korea's pursuit of nuclear weapons.
The Security Council may slap Pyongyang on the wrist, as it has before, but China, a permanent member, has often stood in the way of strong international action.
But it remained unclear exactly what the West would be able to do. President Bush pressed for similar sanctions after the North's nuclear test in October 2006, but they had little long-term effect.
Obama also said that he still planned to continue plans to pursue missile defence, but he tied the need for such a system to any Iranian acquisition of nuclear weapons.
Russia opposes locating a defence shield in Poland and the Czech Republic, as current plans call for, and Obama said in a letter to Russian President Dmitri Medvedev two months ago that if Russia were able to help the US stop Iran from getting a nuclear weapon, there would be no need for a missile defence shield in Eastern Europe.
The issue has particular resonance here in Prague, since the now collapsed government of Prime Minister Mirek Topolanek went to bat against popular opinion here to support the missile shield, only to have the Obama administration begin to walk back from the plan.