Ayman al-Zawahiri has been appointed the new leader of al Qaeda, according to a statement posted on jihadist websites.

Al-Zawahiri has played a defining role in al Qaeda for more than a decade as Osama bin Laden’s deputy. Even before the announcement, he had been widely regarded as the organization’s de facto leader.

The announcement, dated June 2011 and which surfaced Thursday on the sites, said the decision to appoint al-Zawahiri was made to pay respect to the “righteous martyrs” and to honor the legacy of bin Laden.

Bin Laden was killed last month in a U.S. raid on his compound in Abbottabad, Pakistan.

CNN cannot authenticate the statement, but it appeared on radical Islamist sites known for posting similar statements and recruitment videos by other al Qaeda figures.

“Hereby the General Command of the Qaida al-Jihad — and after the end of the consultations — we declare that Sheikh Dr. Abu Muhammad Ayman al-Zawahiri (May God bless him) will take over the responsibility of command of the group,” the statement said.

It also said the group will not shift its policy and pledged its support to, among others, Mullah Mohammed Omar and the Taliban as the latter battles the U.S. and NATO presence in Afghanistan.

(Source: CNN)