Washington: Following the killing of Atiyah abd al-Rahman, Al-Qaeda's second-in-command, it would be difficult for its new leader Ayman al-Zawahiri to consolidate his control over the terror outfit, an official has said.
Zawahiri had taken over as the Al-Qaeda leader after Osama bin Laden was killed by US forces in a special operation in Abbottabad area of Pakistan on May 2.
Atiyah, a Libyan national, was killed by a US drone strike in the Waziristan area of Pakistan on August 22.
"Zawahiri needed Atiyah's experience and connections to help manage al Qaeda. Now it will be even harder for him to consolidate control," an US official said on condition of anonymity.
"There's no question this is a major blow to al Qaeda. Atiyah was at the top of al Qaeda's trusted core. He ran daily operations for the group since Shaykh Sa'id al-Masri was killed last year, and has been Zawahiri's second-in-command since Bin Laden's death in May," said the official.
Atiyah was the one affiliates knew and trusted, and he spoke on behalf of both Osama bin Laden and Zawahiri, the official said.
The State Department had offered up to USD 1 million for information about him.
"He planned the details of al Qaeda operations and its propaganda. His combination of background, experience, and abilities are unique in al Qaeda—without question, they will not be easily replaced," said the official, who requested anonymity.

US counter-terrorism officials believe that Atiyah's death is a tremendous loss for Al-Qaeda as Zawahiri was relying heavily on him to help guide and run the organization, especially since Osama's death.
Counter-terrorism officials point out that it is the treasure trove of materials obtained from the Abbottabad compound of Osama bin Laden which led to the killing of Atiyah.
These documents showed clearly that Atiyah was deeply involved in directing Al-Qaeda's operations even before the raid.
"He had multiple responsibilities in the organization and will be very difficult to replace", the official added.
Brian Fishman, a Counterterrorism Research Fellow at the New America Foundation, in a blog post for the Foreign Policy said that Atiyah's death, if confirmed, will hasten the demise of al-Qaeda as a functional covert network.
"Although one must assume Atiyah prepared for his death, his contacts must nevertheless now wonder what US intelligence personnel knew his activities and communications that might now put them at risk," he said.
Fishman said Atiyah's central role in the al-Qaeda network has been clear since the Combating Terrorism Center at West Point in 2006 released a declassified letter from Atiyah to al-Qaeda in Iraq (AQI) leader Abu Mus'ab al-Zarqawi.
"That letter indicated not only that Atiyah had been an influential player in jihadi circles for years, but that he had a freedom of movement from Pakistan into Iran that was, if not unique, then very rare," he said.
"Such freedom of movement was important not just for communications with Zarqawi and the al-Qaeda faction in Iraq, but for communications from al-Qaeda members held under house arrest in Iran, most importantly Sayf al-Adel, who has continued to play a key strategic role for al-Qaeda despite not having absolute freedom," Fishman said.