Al-Qaeda’s core in Pakistan is the most formidable terrorist organisation threatening the US, despite the terror outfit suffering some notable setbacks in 2009, a top US counter-terrorism official has said.

“Al Qaeda’s core in Pakistan remained during 2009 the most formidable terrorist organisation targeting the US. It has proven to be an adaptable and resilient terrorist group whose desire to attack the US and US interests abroad remains strong," said Daniel Benjamin, the State Department's counter-terrorism coordinator.

"We assess that Al Qaeda was actively engaged in operational planning against the US and continued recruiting, training and deploying operatives, including individuals from Western Europe and North America," Mr Benjamin told reporters at a State Department news conference.

Releasing the annual State Department Country Reports on terrorism for 2009, he said Al Qaeda suffered some notable setbacks in 2009. “The group remained under great pressure in Pakistan due to Pakistani military operations aimed at eliminating militant strongholds in the Federally Administered Tribal Areas," he said.

"Al Qaeda faced a number of significant leadership losses; and, as a result, found it more difficult to raise money, train recruits, and plan attacks outside of the region,” Benjamin said.

At the same time, the group also continued to suffer from widespread Muslim disaffection due to recent and past indiscriminate targeting of Muslims by its operatives and allies in Algeria, Iraq, Saudi Arabia, Pakistan, Indonesia and elsewhere. The number of conservative clerics and former militants speaking out against the organisation has increased considerably, he said.

Despite these setbacks to the core leadership, the broader Al Qaeda threat has become more dispersed and more geographically diversified, which served partially at least to offset the losses suffered by the core group, he said.

“We saw this most dramatically with the attempted December 25th bombing of a US commercial airliner destined for Detroit. This incident demonstrated that at least affiliate, Al Qaeda in the Arabian Peninsula, has not just the will but also the capability to launch a strike targeting the US at home,” Benjamin said.

The assumption that Americans have some special immunity to Al Qaeda's ideology was dispelled during the year, he noted. “While our overall domestic radicalisation problem remained significantly less than in many Western nations, several high-profile cases demonstrate that we must remain vigilant,” he said.

Five Americans from nearby Virginia were arrested, tried and found guilty in Pakistan of terrorist-related offences. “We have also seen Americans travelling to Somalia to join al-Shabab,” he said.

“We’ve also seen Americans rise to prominence as proponents of violent extremism. The native California, Adam Gadahn, has become an Al Qaeda spokesman, enabling the group to increasingly target its propaganda to Western audiences,” he said.

“Omar Hammami, an American who grew up in Alabama, has become an important Al Shabab voice on the Internet. The most notable of these, however, is Yemeni-American Anwar al-Awlaki, who has catalysed a pool of potential recruits that others had failed to reach,” Mr Benjamin said.

“We are urging our partners around the world to adopt a no-concessions policy towards hostage-takers so that we can diminish this alternative funding stream in these different regions,” he said.