A spokesperson of Al-Qaeda has yesterday claimed responsibility for the killing of former Pakistani prime minister Benazir Bhutto, Italian independent news agency Adnkronos International (AKI) said.

"We terminated the most precious American asset which vowed to defeat the mujahadeen," Al-Qaeda's commander and main spokesperson Mustafa Abu Al-Yazid told AKI in a phone call from an unknown location.

Al-Yazid, who is the main Al-Qaeda commander in Afghanistan, said that the decision to kill Bhutto, who is the leader of the opposition Pakistan People's Party (PPP), was made by al-Qaeda number two Ayman Al-Dhawahiri in October this year, according to AKI.

Bhutto had just addressed a pre-election rally yesterday in the garrison town of Rawalpindi when a suicide bomber blew himself up.

At least 15 other people were killed in the attack and several others were injured.

Al Qaeda already took responsibility for the first unsuccessful attempt on Bhutto's life back in October.