Yemen-based al-Qaeda in the Arabian Peninsula said last week that it had trained and equipped Abdulmutallab, 23, for the plane plot.
Earlier this week, in a statement to the UK parliament, Alan Johnson, the country's interior minister, said: "As has been widely reported, Abdulmutallab attended University College London (UCL) between 2005 and 2008, where he completed a degree in engineering.
"During this time he was known to the Security Service but not as somebody engaged in violent extremism.
"His family and friends have stated their belief that he turned to this during his time in Yemen."
On Thursday, a spokesperson for UCL said: "We would like to reiterate that there is absolutely no evidence at this stage to suggest that Umar Farouk Abdulmutallab was radicalised at UCL.
"We are currently providing all assistance to the authorities, and are setting up a full independent review of Mr Abdulmutallab's time here."
Mohamed Vall, Al Jazeera's correspondent in Sana'a, the Yemeni capital, said: "There are two major points that he [al-Alimi] made today that shed new light on the incident.
"One of them is that he [Abdulmutallab] was not recruited in Yemen, and the other is that he did not bring these explosives from Yemen, he brought them from Nigeria.
"This of course takes some of the burden from the Yemenis and takes it to London."
Vall said that the international focus on Yemen was of increasing concern to the government in Sana'a.
He said: "There are fears that if there is more and more interference from the outside world, that could make a situation that is already fragile in this country ... worse."
Yemen, which is trying to fight a resurgent al-Qaeda on its territory, launched an operation this week to root out al-Qaeda fighters who they said were behind threats that forced several Western embassies to close on Sunday.
|Brown said Britain planned to join the US in funding an 'anti-terrorist' force in Yemen [AFP]
Last week, Gordon Brown, the British prime minister, said the UK planned to join the US in funding an "anti-terrorist" force in Yemen.
Brown said he would hold a meeting in London on January 28 to discuss how to counter radicalisation in Yemen.
Abubakr al-Qirbi, Yemen's foreign minister, whose country is also facing a Houthi uprising in the north and simmering separatist sentiment in the south, has rejected direct foreign intervention.
"We think this is the priority and the responsibility of our security forces and the army," al-Qirbi told CNN, the US broadcaster.
Asked by CNN whether Yemen would accept direct US intervention, al-Qirbi said: "No, I don't think we will accept that.
"I think the US, as well, have learned from Afghanistan and Iraq and other places that direct intervention can be self-defeating."
Al-Qirbi said there were about 200 to 300 al-Qaeda operatives in Yemen.
"I think our thought was that maybe we should spare al-Qaeda in the last year because of the confrontation in the south and with the Houthis.
"But al-Qaeda took advantage of that," Qirbi said, adding that al-Qaeda had tried to make inroads with northern fighters and southern separatists.
Meanwhile, gunmen shot dead two Yemeni soldiers in attack on a police station in Aden, the former capital of south Yemen, witnesses and security sources said on Thursday.
The gunmen were believed to be suspects wanted in criminal cases, an independent Yemeni news website reported, quoting a security official.