WASHINGTON: The White House has called North Korea's latest nuclear test a ''highly provocative act'' that threatens US security and international peace.    

In a statement issued early Tuesday, President Barack Obama promised to ''continue to take steps necessary to defend ourselves and our allies''.

He also urged ''swift and credible action by the international community''.

North Korea said it successfully detonated a miniaturised nuclear device at a northeastern test site Tuesday, defying UN Security Council orders to shut down atomic activity or face more sanctions and international isolation.

Obama said such efforts ''do not make North Korea more secure''.

Instead, he said, North Korea has ''increasingly isolated and impoverished its people through its ill-advised pursuit of weapons of mass destruction''.