Washington: The North Korean launch of a rocket on Sunday was a "provocative act", says US President Barack Obama.
Pyongyang fired what it said was a communications satellite around 11:30 am (0230 hrs GMT) from North Korea's east coast, but Japan, South Korea and Washington believe the launch was a screen to test a long-range ballistic missile.
"North Korea's development and proliferation of ballistic missile technology pose a threat to the north-east Asian region and to international peace and security," Obama says in a statement issued from Prague, where he is to attend a US-European Union Summit Sunday.
The White House said the launch of what it identified as a Taepodong 2 missile was in violation of a United Nations Security Council resolution that bans Pyongyang from conducting ballistic missile activities.
"With this provocative act, North Korea has ignored its international obligations, rejected unequivocal calls for restraint, and further isolated itself from the community of nations," Obama adds.
The US President said the US would work with allies, including Japan and South Korea, to bring the issue to the Security Council. Tokyo had already requested an emergency meeting of the body in New York.
"I urge North Korea to abide fully by the resolutions of the UN Security Council and to refrain from further provocative actions," Obama adds.
The US remains committed to the six-party talks to halt North Korean nuclear activities.
State Department spokesman Fred Lash says the launch "prompts the United States to take appropriate steps to let North Korea know that its development, deployment and proliferation of ballistic missiles, missile-related materials, equipment and technologies, pose a serious threat to the north-east Asian region and to the international community."