US President Barack Obama has for the first time publicly accused a group linked to al-Qaeda over the attempt to blow up a plane bound for Detroit from Amsterdam on Christmas Day.
Mr Obama said it appeared al-Qaeda in the Arabian Peninsula, which is based in Yemen, armed and trained Umar Farouk Abdulmutallab, 23, of Nigeria.
The BBC reports the group admitted responsibility in an internet statement last week.
Mr Obama said Abdulmutallab travelled to Yemen where he was equipped, trained and directed to carry out the attack.
In a weekly radio and television address on Saturday, he said the United States will continue to work closely with Yemen to fight against terrorism.
Abdulmutallab, who is now being held in a federal prison, is accused of trying to detonate explosives strapped to his body as the plane, with nearly 300 people on board, prepared to land on 25 December.
He had flown from Accra in Ghana, to Lagos and then to Amsterdam.
Yemen to attend conference
Meanwhile, Yemen says it will attend an international meeting called by Britain to discuss how to combat Islamic militancy in Yemen.
British Prime Minister Gordon Brown says countries the way countries share information on suspected terrorists, must be urgently tightened.
The conference will be held in London on 28 January.
State media in Yemen report top US General David Petraeus has met President Ali Abdallah Saleh.
The general - who is responsible for US Middle East and Central Asian operations - reportedly said the US was keen to support Yemen's fight against al-Qaeda.
Yemeni officials said more troops have been sent to fight rebels in the east.