"Now justice has been served and this terrorist leader is gone,"
said in a televised address on August 1.
Earlier, the White House announced that the United States conducted a successful counterterrorism operation against a "significant" al-Qaeda target in Afghanistan over the weekend.
Biden said US intelligence officials tracked
to a home in central Kabul where he was hiding with his family.
The operation was performed on July 31.
71-year-old Zawahiri led the terrorist attacks on the United States on September 11, 2001, together with
Osama bin Laden
, the founder of Al-Qaeda.
Bin Laden and al-Zawahiri fled US forces in Afghanistan in late 2001, and Zawahiri's whereabouts have long been a mystery.
Zawahiri took over as al-Qaeda leader after bin Laden was killed in a 2011 US raid in Pakistan.
It was Zawahiri who was the chief ideologue of the global terrorist network Al-Qaeda for several decades and played a central role in the attacks on the US embassies in Kenya and Tanzania in 1998, three years before the 9/11 attacks that killed nearly 3,000 people.
American intelligence determined with "high confidence" that it was Zawahiri who was killed.
There were no other victims.
There have been several rumors of Zawahiri's death in recent years, and he has long been reported to be in poor health.
His death raises questions about whether the Taliban provided sanctuary to the al-Qaeda leader after taking over Kabul in August 2021.
A US official said that high-ranking Taliban officials were aware of his presence in the city.
, the former director of the CIA, said the fact that Zawahiri was in Kabul showed that the Taliban had "not learned their lesson" after harboring bin Laden when they ruled Afghanistan in the late 1990s. years.
"It really reflects the continuing close relationship that obviously still exists between al-Qaeda and the Taliban," Petraeus said on CNN.
Taliban spokesman Zabihullah Mujahid, in response to the killing of al-Zawahiri, said that the Afghan authorities strongly condemned the attack as a "violation of international principles" and the 2020 agreement on the withdrawal of US troops.
The drone strike was the first known US strike inside Afghanistan since US troops and diplomats left the country in August 2021.
Then the hope for trained Afghan soldiers failed - the Taliban regained full control over the country in just a few days.