WASHINGTON --President Barack Obama on Monday expressed grave concern over North Korea's nuclear test.

Here is the text of his statement:

Today, North Korea said that it has conducted a nuclear test in violation of international law. It appears to also have attempted a short range missile launch.

These actions, while not a surprise given its statements and actions to date, are a matter of grave concern to all nations.

North Korea's attempts to develop nuclear weapons, as well as its ballistic missile program, constitute a threat to international peace and security.

By acting in blatant defiance of the United Nations Security Council, North Korea is directly and recklessly challenging the international community.

North Korea's behavior increases tensions and undermines stability in Northeast Asia. Such provocations will only serve to deepen North Korea's isolation. It will not find international acceptance unless it abandons its pursuit of weapons of mass destruction and their means of delivery.

The danger posed by North Korea's threatening activities warrants action by the international community. We have been and will continue working with our allies and partners in the Six-Party Talks as well as other members of the U.N. Security Council in the days ahead.

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