Updated

British Prime Minister Gordon Brown has called for a high-level international meeting on Jan. 28 to devise ways to counter radicalization in Yemen.

He says the meeting would be held at the same time as a planned international conference on Afghanistan to be held in London.

Yemeni security officials have said a Nigerian suspected in the recent attempted attack on a U.S. airliner had stayed on in Yemen illegally after his visa expired three months ago and should have been stopped by authorities from leaving the country.

Umar Farouk Abdulmutallab spent time in Yemen on two occasions before the attempted Christmas Day attack on a Detroit-bound Northwest Airlines flight, and Al Qaeda has claimed responsibility for the attempted attack.

Brown says an international approach is needed to combat the rising influence of Al Qaeda in Yemen.

The prime minister said Friday he hopes the meeting will coordinate donor efforts to help the government of Yemen and identify counterterrorism needs there.

He says the meeting plan is backed by the United States and the European Union.

Yemeni officials said Abdulmutallab's student visa for Yemen, where he studied Arabic at a local language institute, was valid from Aug. 4 to Sept. 21.

After his visa expired, the 23-year-old stayed on in Yemen until the first week in December, they said, but his whereabouts in the country is unknown.

They added that Yemen's airport authorities and passport control should have prevented Abdulmutallab from departing. The officials spoke on condition of anonymity because they were not authorized to discuss the case with the media, pending the outcome of an investigation.

The probe will look into why the Nigerian wasn't detained, questioned and prohibited from leaving the country, they said.