HONOLULU ?US President Barack Obama on Saturday accused an Al-Qaeda affiliate in Yemen of arming and training a young Nigerian man for a thwarted suicide mission to blow up a US airliner.

Obama, in his weekly radio and video address posted on the White House website, promised to hold the group, Al-Qaeda in the Arabian Peninsula, to account for the attack, declaring the United States was at war with a "far-reaching network of violence and hatred."

"We know that he traveled to Yemen, a country grappling with crushing poverty and deadly insurgencies," Obama said, referring to the suspect Umar Farouk Abdulmutallab.

"It appears that he joined an affiliate of Al-Qaeda, and that this group Al-Qaeda in the Arabian Peninsula-trained him, equipped him with those explosives and directed him to attack that plane headed for America."

Without categorically pointing to Al-Qaeda as the one behind the Northwest attack, US officials had earlier noted a "linkage" with the terror group.