Obama warns N Korea it will take steps to protect allies
12 April 2013 Last updated at 02:28 BST
President Obama has added his voice to the calls of world leaders demanding that North Korea must change course or face the consequences.
G8 foreign ministers meeting in London threatened new sanctions if Pyongyang continues to develop nuclear weapons and ballistic missiles.
Speaking at a joint news conference with UN Secretary General Ban Ki-moon, Mr Obama warned that Washington would take "all necessary steps" to protect America and its allies.