Washington:  Al-Qaeda leader Ayman al-Zawahiri called on Algerians to overthrow the government of President Abdelaziz Bouteflika, and praised Libyan rebels for seizing Tripoli, in a new video.

Osama bin Laden's successor Zawahiri urged Libyans to adopt sharia law as they rebuild the country after the NATO-backed rebels' ouster of longtime leader Muammar Gaddafi.

"The first thing that this NATO will ask of you is to relinquish your Islam," Zawahiri said according to a translation provided by US monitoring service SITE, dismissing the military alliance as a "Western gang".

"Be careful of the plots of the West and its henchmen while you are building your new state. Don't allow them to deceive you and steal your sacrifices and suffering."

Zawahiri, wearing white, was shown sitting in a cloth-covered chair in front of a green backdrop in the 13-minute video released on extremist forums on Tuesday, SITE said.

The veteran Egyptian militant and long-time Al-Qaeda number two took over the jihadist network after bin Laden was killed in a clandestine raid by US Navy commandos in Pakistan on May 2.

"And if I congratulated our people in Libya for their victory over the tyrant, I call upon our people in Algeria to follow their footsteps," Zawahiri said in the video.

"Here are your brothers in Tunisia and then in Libya having thrown out the two tyrants to the trash can of history, so why don't you revolt against your tyrant?"

Bouteflika's government has faced protests resembling those that ousted neighbouring Tunisia's dictator Zine El Abidine Ben Ali, but the protest movement has been successfully contained by security forces.

The video is the latest in which the militant chief, who is now Washington's most wanted man, has attempted to seize on the "Arab Spring" revolutions.